Looking to start SFP, need help

I am a long time seller on Amazon, but I am looking to start a few of my listigs with SFP.

I have the Prime Trial set up. The problem I have is, where I am based, my Tracked 24 items sometimes take 2 days to arrive rather than one. Is there anything I can do about this to avoid it damaging my Prime trial?

I’m very nervous to start, but I also think it could lead to better sales, so any help would be appreciated.