Heat retention and floor retention

Two questions, one post.

First, for long pizza cooks 20 pizzas…2 hours - does your floor temperature hold enough heat or do you need to bring the fire back over your bricks and bring the temp back up? Assuming 6 minutes a pizza by the time you load, stretch, reload.

2nd. How good is your oven at retaining heat? I get mine well above 1000 but by the next day it is below 300. (Last pizza 9:00 pm, next day check at 10:00 am) Is this because I don’t have a damper? I will say, underneath the oven is warm/hot. I am wondering if I should have added a layer of calcium silicate board