Update from 1.5.3 to 2.0: Error loading blockchain even if I was on the good one, but after redowloading your, it's fine now

About the stake age set to 1 day, it's for new coin generated after update only ?
No all coins, but doesn't effect until after the block 5667000 .
Best hash right now:
SetBestChain: new best=ef68f741ec495654d34e height=5652466 trust=87692314699589 blocktrust=19509069 date=09/10/17 12:34:29