Does 1 day after release date considered release date, own different category or a non-release date?

When i was in uc with my friend and looking for some tanuryns

Somebody offered him a nm random release date tanuryn to buy

They negotiated on the price and settled for 10m (quite the ovp and told him about it but he really wants it so i let him be🥀)

When the seller put it on queue i checked it's info card i saw that it was september 26

Told him about it and he still insisted on buying it since he argued that when the tanuryn dropped it's already 26th for us thus it still considered release date

Any thoughts on this?