I have a ps5 and played the ps4 version but just upgraded to the

PlayStation 4 - Wikipedia

PS5 Firmware 5.00 (22.01-05.00.00) and PS4 Firmware 9.50 released - As always, avoid updating if possible

Can you play PS4 games on PS5? PlayStation backwards compatibility

PS5 - PS4 backward compatibility, PS4-to-PS5 upgrades detailed [Update] - Gematsu

PS5 w/ Disc - Just bought new PS4 version of the Game, Cannot upgrade to PS5 version : r/PlayAvengers

PS5 Backwards Compatibility: How to Play PS4 Games on PS5

PS4 to PS5: All Games with Confirmed Free Upgrades

PS4 and PS5 owners can get free Apple TV+. Here's what you need to know

PS4 Pro vs PS5: Should you upgrade?

PS Now's New Games Are PS4 Only, Sony Confirms No PS5 Upgrade Path

PS4 vs PS5: Is it time to upgrade?

I have a ps5 and played the ps4 version but just upgraded to the ps5 version do I need to keep both or can I delete the ps4 version : r/elderscrollsonline

PS5 details: games, price, release date, backward compatibility, and more - Polygon