EDIT: Here's the updated timeline that I've developed using ideas that I've come up with over the last few months. It clarifies some events, changes some so that they make more sense, and adds in new ones.
2008:
-Since the success of Operations CHERRY BLOSSOM and SLEDGEHAMMER, 15 of the 21 Hives on Earth have been retaken and destroyed by human forces. Only the Hives in the northern Soviet Union and in Central Asia remain under BETA control.
-Western Europe has been full retaken, at the cost of tens of thousands of troops and hundreds of TSFs. Lyons, Budapest and Belarus Hives retaken.
-The Lockweed-Mardin F-35 Lightning II is given its first combat tests in real combat, during Operation Khaki, the assault on Objective 13 in India.
-Development of US Navy heavy TSF begins, as the F-24 Project. Navy planners settle on a heavily modified and adapted version of the F-22, co-developed by. This is the last purely US-developed TSF.
2009:
-December: UN, US, COSEAN, Australian and Japanese forces assist the United Front of China in taking the Dunhuang Hive.
2011:
-May: The Soviet Union collapses due to massive civil uprising amongst the surviving civilian population in Alaska and Ireland. The uprising is supported by rebellious significantly large elements of the Soviet Army's enlisted and TSF forces. The newly founded Commonwealth of Independent States places itself under United Nations jurisdiction.
2012:
June: The final hive, Objective 15, the Krasnoyarsk Hive, is taken by the combined forces of 8 different militaries. Mankind collectively celebrates as the world's militaries begin clean-up operations around the globe.
November: Preparations begin for retaking Luna. Orbital facilities are upgraded in the build-up. The now-redundant colony ships that were built for the Alternative V plan are repurposed as orbital assault carriers. The ships are retrofitted with two dozen EML-99 railgun turrets each for fire-support.
2013:
-Research into modifying existing TSFs and combat vehicles for combat in vacuum, since most existing technology is based around working in atmosphere. Since the last engagement on the moon was in the 1970's, pre-existing equipment is long out of date, and a lengthy redevelopment is required. As such, the upgrades are limited to 3rd Generation TSFs, and modern combat vehicles. TSF Jump Unit jet engines are replaced with aerospike rocket motors and manoeuvring thrusters, and ground support vehicles such as tanks and rocket-launch systems are modified to be fully air-tight and electrically powered.
-The construction of additional XG-70 units is shelved, after the loss of the units used during Operation 21st and Operation OUKA , and the inability of existing computer systems to control the immense fluctuations in the G-Element produced gravity field.
2016:
-Orbital trials with space modified TSFs prove highly successful. Production of the F-15F Star Eagle, F-22B, F-24B Lynx, F-35D War Lightning, Type-14 Yukikaze, EF-2020 Cyclone, and JAS-39+ begins.
-Rebuilding of damaged areas of the world begins. It is expected to take at least 30 years to rebuild and repopulate Europe alone.
2017-2020:
-build up to Operation: MOONLIGHT continues, with hundreds of space-combat TSFs being built, and thousands of older models being modified to take part in the assault, along with tens of thousands of ground support vehicles. Over 300,000 personnel are retrained and equipped for orbital and lunar combat.
-Another 8 Assault Carriers are constructed in addition to the three existing carriers, bringing the total to 11.
2021:
-February-May: Troops, equipment, vehicles and supplies begin transferring aboard the carriers.
~Side Note – Carrier Names: UNS Spirit of Humanity, UNS Gaia, UNS Kashgar, USS Enterprise, USS Freedom, HMS Illustrious, EUS Ignis, CNS Warsaw, IJN Tsukikaze, HMANZS Gallipoli, UFS Yǔzhòu.
-July 23rd: The Lunar Fleet departs Earth.
-July 25th: The Lunar Fleet arrives in lunar orbit. The ships begin bombardment of the nearside hives with railguns and conventional warheads. Ground forces begin deployment.
2025:
-After four years of combat, the final hive on the moon is taken. Humanity's sights are now set on Mars, the world where the BETA were first encountered.
-Magnetic accelerator-based weaponry becomes the standard for infantry, light and armoured vehicles, and for TSFs.
2026:
-The mothballed Alcubierre Drive prototypes developed for Alternative V are brought out from storage. The drive primarily relies on G-11, which controls gravity, and G-6, which has negative mass, to generate the space-time bubble theorised by the Mexican physicist Miguel Alcubierre. The first full scale test carries the test vessel, the Voyager, out to Pluto within thirty minutes.
-After further testing, the drives are mass produced and fitted to the Assault Carriers that were originally destined to carry them.
2028-2035:
-The Martian Campaign: Characterised by its heavy initial casualties, and an astoundingly high rate of attrition for equipment, the Martian campaign is the most brutal and punishing ever undertaken by human forces since Operation OUKA, and is not surpassed for over 150 years. During the Elysium campaign of 2031 alone, more than 2000 vehicles, including over 300 TSFs and TSAs, are lost in only two months of vicious fighting. Several hives are blasted to bedrock from orbit using railgun-driven thermonuclear warheads.
2034-2035:
-The Belt War: 8 TSF battalions and their attendant Orbital Marine units and Assault Carriers are tasked with wiping out BETA holdouts in the Asteroid Belt. Several Hives are cleared on Ceres, Vesta and Pallas, while a few smaller Hives on lesser rocks are simply atomised. Casualties are heavy, and many troopers are lost to the void. Bodies continue to be found for the next hundred years.
2035:
-The Jovian Moons Campaign.
2037:
-The Europa Incident: The hundred and fifteen strong 31st Amphibious Assault Battalion Trident is killed to the last as their A-14 Morgen's hold the line against massive hordes of adapted BETA that emerge from hives in the submarine bedrock of the ice moon. Although the pilots of Trident Battalion die one by one, alone in the dark, not a single BETA organism reaches the surface. Less than a quarter of wrecks are able to be recovered from the Europan world-ocean.
2040:
-After almost 70 years of fighting, the Solar System is finally cleansed of BETA.
2046:
-The first fusion power-plant is constructed. After some significant hiccups, the installation proves a great success.
2050:
-Colonies set up on Luna and Mars, using the structurally intact Hives as the basis for new underground cities. Space travel becomes commonplace.
2054:
-small scale fusion generators are developed, alongside fusion-powered engines for vehicles, such as aircraft and TSFs.
2061:
-a new form of TSF is developed as a significantly smaller and cheaper vehicle for infantry support and urban combat. Colloquially known as the Patrol Fighter, Recon Fighter or Utility Fighter ("Ute"), the first microTSF, the F-42 Phoenix, enters service in the militaries of several nations.
2063:
-July: The UN assimilates the world governments into a single, unified body. There is some conflict, but most of the major powers accept the decision to unify.
2060's:
-the human population finally begins to approach pre-BETA levels.
-Because the threat of Laser-class BETA has been passed for over 20 years in the Sol System, fighter and tactical strike aircraft are gradually reintroduced into world militaries. Many design philosophies from TSFs are incorporated, since fighter design has been stagnant since 1967, with the original F-4 Phantom, prior to it being redeveloped as a TSF. The UN Air Force is established.
-The UN Navy Fleet is increased in size and diversity, with newer classes comparable to old wet Navy ship types introduced into the Fleet. Frigates, Destroyers, Cruisers and Battleships enter production alongside Carriers, which once again carry fighters and strike aircraft.
-FTL equipped ships launch to colonise nearby systems. Barnard II, later named Haven, is among the first colonised, since it was known to be habitable back in the 20th century. Also discovered are several worlds in the process of being devoured by the BETA. The ones that are nowhere near habitable are scoured with fusion bombs, while habitable ones are invaded, the Hives purged, and the planets fortified. Several of the worlds are found to have traces of now-extinct civilisations, most of which are found on BETA devoured worlds. However, some are found to have been obliterated by what is later thought to have been orbital bombardment.
-Several planets are found to have still surviving non-human populations. However, only the [Fythern] of Ishtar, the [Voron] of Eridanos, and the [Sabaka] of Lupus have the numbers to constitute viable populations, due to their high reproductive rates. The fates of the Vulcanian [Ekara], Abydonian [Tanin] and Tribunite [Ari] are used to quell civil unrest regarding the existence of alien races that are not BETA strains.
2075:
-The remains of what appear to be alien buildings are discovered on Mars. Buried amongst the rubble, the wreckage of several ships is discovered. The scientific community and the major military powers are extremely suspicious of the ruins. Traces of an unidentified substance are found on what are believed to be the drive cores of the ships. Further testing reveals that the substance alters the mass of objects by way of positive and negative electrical charges, similar to certain strains of G-Elements. The substance is later named "Element Zero" -"Eezo" for short- due to it's curious atomic properties. The samples are sealed away, since not enough is found to be of any practical use.
2077:
-Engineers and scientists working on military stealth technology make a significant breakthrough. They develop an optical cloak system that renders the user almost completely invisible to the eye, as well as most infrared wavelengths. Testing using preserved Laser-class samples prove that the cloak works against them. Unfortunately, the Camouflage Field is found to draw a ridiculous amount of energy for its operation, and that they are extremely temperamental. Testing continues.
2079:
-A survey ship investigating Pluto accidentally activates an alien artefact buried beneath the surface of Charon. The artefact thaws, melting a significant portion of Charon, reducing the size of the moon by almost 15 percent and briefly giving it an atmosphere.
-A single ship, the UNS Yukon, captained by Commander Jon Grissom, approaches the artefact, while being observed by a dozen other ships. There is a flash of light, and the Yukon disappears. It reappears several hours later, where it finds the UN Fleet guarding the device about to obliterate it with G-bombs. The crisis is averted, with Commander Grissom barely managing to talk down the commander of the UN fleet.
-Survey data from the Yukon reveals that the ship's destination was in the Arcturus System, 36 light years away.
2080:
-further surveys of Arcturus reveal the existence of another 5 Relays in the system. Exploration of the Relay network begins by the UN. Large amounts of Element Zero are also discovered on the third planet of the system, leading to questions from the scientific community concerning whether or not it is naturally occurring. Eezo experiments become somewhat rampant. However, very few practical implementations become apparent for many years.
-Construction of Arcturus Station and Eunomia Fleet Base begins.
-The first self-aware AI, named Eve, comes online. Once she begins to ask "The Question", her creators opt to leave her to find an answer for herself.
2082:
-The first TSF built around an Electronic Camouflage Field (ECF), the F-45 Spectre, enters service, supplanting its short-lived predecessor, the F-44 Raven. The success of the system leads it to being adapted for every land and aerospace vehicle larger than an AFV.
2083:
-Eve declares to her creators that she believes herself to be alive. More AI's are created.
-The Synthetic Rights Laws are passed, granting AI's the same rights as humans.
2085-2120:
-Local exploration slows as exploration and colonisation efforts focus towards the mapping of the Relay Network, although ships are sent to continue mapping nearby systems.
2121:
-Eden Prime in the Utopia System is settled.
2128:
-Remnant in the Vale System is settled.
2130:
-Yozora in the Night's Edge System is settled.
2132:
-Terra Nova in the Asgard System is settled.
-Corvus in the Talon System is settled.
2130's:
-Fleet Reorgaisation: The 7th through 14th Fleets are reassigned to the new Colonies established in the Relay network. While they are still officially based and administered in their home systems, the Fleets former duties are now covered by the 4th, 5th and 6th Fleets.
2157:
-A BETA infestation is discovered on a habitable world that is named Shanxi, which reveals the extent of the BETA infestation, since Shanxi is over 50 light years and three Relay jumps from Earth. The infestation is also new; with only three hives constructed. Two carriers, a cruiser squadron and a frigate/destroyer flotilla are assigned to assist in taking the hives and securing the planet for possible colonisation.
-Anomalous signals detected from the Shanxi Theta Relay. A ship is sent to investigate, but nothing is found.