making quiche ahead of time

I would blind bake the crust the night before and mix the egg filling and keep that covered in the fridge overnight.
Then morning of bake them while you’re getting ready and such.
Quiche really does suffer when rewarmed, if tou do bake the night before i would bring as is and serve room temp, skip the warming since they won’t be warm by the time you reach your destination.

I've done this for various reasons. The main problem is to avoid soggy crust syndrome, as the wetter filling soaks into the crust. You can help avoid that by brushing the raw crust with a bit of egg white, and adding a layer of something like parmesan cheese, and baking the crust until it's beginning to take on color. Then fill and finish the baking. Cool them, chill in the frig, and ready for the next day. Quiche is actually intended to be eaten either slightly warm or at room temperature- so whether you decide to heat them is up to you. When I do heat them, I do it according to Miss Martha's advice: 325 for 15 minutes as Half Pint mentions.

Ms. Martha suggests covering with aluminum foil and reheating in a 325F oven for 15 minutes:
https://www.marthastewart.com/353223/quiche

I'm afraid that quiches respond particularly badly to this kind of treatment.