How would you check if a players data contains something from a specific date?

[RockGodDev]

Basically, I have a tower defense game, in it, there are limited units. One of those units recently returned for in-game currency, but since that wouldn’t be fair to the OG players who got the limited unit on release, I’d like to award them a skin.

The unit wasn’t obtainable for ~3-4 months, so how would I check if the players data contains the original limited unit, and not the newly bought one that got rereleased?

[GamEditoPro]

You can diffirentiate them if you make some sort of timestamp on when they were obtained. Cuz your situation has 2 main points, when player loads, mark them so they had that unit, and give reward. If player got it later, he won’t have this mark, and no reward will be given out.