When does the premium period starts when buying a premium pack?

Hi, i just bought a premium pack and wanted to know if i can wait to get my premium status cause i have a tryp tomorrow

No sadly you can not put off your premium time. There’s already been a suggestion for it however idk if it’s been added. Sorry for you not being able to use it all. It happened to me a few weeks ago when I bought the wyvern. I lost my last 3 days because I was moving