I was playing thru Fallout 3 for probably the 10th time and noticed something this time thru at Vault 112 that I hadnt really thought about before. When you first enter, the robot informs you you are 202.3 years late. That would mean that the folks who entered that Vault did so sometime in mid 2075, 2 years before the great war even happened. Did none of these people's family's wonder what happened to them ? Did no one notice 85 people went missing suddenly ? Were they brought in believing the war was happening ?

My guess is they reserved spaces in the Vault before the Great War, like every other (one of the Keller tapes mentions trying to get into a Vault - "101, 87, all full to capacity..."), unaware of what was in store for them.

Since you can't be sure when the bombs would drop the idea was probably 'better safe than sorry' - you obviously need to be sealed in the Vault when the bombs drop to be guaranteed survival, explaining the 2 year gap.

When Vault Tech didnt know the exact date, maybe they programmed the vault with one they estimated...

Or maybe, the whole war was just a conspiracy!

Yep thats the most likely