Can I make my (vegan) coconut whipped cream ahead of time or will it not keep?

Coconut cream behaves differently than heavy cream. It actually can be stored for 2-3 days, but..it stiffness when refrigerated. You need to take it out of the fridge and when it warms a bit, you re-whip it. It really can get tricky, so it's best to make shortly before serving.

Whipped cream of all kinds tends to deflate as the air dissipates, so better to make it not long before serving.