What does that mean? Reality just shattered, so it's a mish-mash of different time periods.
The people from the Desert region will say it's the early 4th Ancient century.
The people from Ice Age will say it's 9th Modern century.
The people from Small Town will say it's 6th Modern century.
And so on.
And all of them would be right.
The only valid way to keep time is based on an event they can all agree on, which is when the shattering happened. If it's two years after the shattering, we'd call it year 2 AS.