Personally, If I could prove myself as Satoshi, that implies I have the private keys,  I'd rather just cash out some of the coins. I'll probably start at the tail end (closer to present time rather than closer to genesis block.) I'm almost certain Satoshi had been able to mine some later blocks which flew under the radar and not attributable to anyone in particular.

There isn't any evidence or proof (and there could be none at all) but isn't it likely he would have stuck around at least until after the first halving, just to do some test mining and see the reward drop from 50 to 25?

Would probably split the forked coins too.