Temperature Question For A RUB & First Time BP Owner

[Seviper]

Hi guys, so as some of you may know, I am getting a baby BP in a few weeks and I am using a 5L RUB. I'm just having a little trouble keeping the RUB's heating up in the morning, where the basking temp is 87.7F and the humidity is 52%. I decided since I am doing tests, I would spray my RUB two times and immediately close the lid which kicked the humidity up to 56%, but dropped the temperature to 87.3F. Every morning, this part is important, my house is really cold, because the central heating always goes off at nights, and we need to turn the heating back on and wait a couple of hours before the house warms up ( and thus, the temperature in the RUB will go to 88F and higher ), will my soon-to-be snake be alright? I know you should have 88F but it's not really possible in the mornings until the house is heated up...

EDIT :: 1 hour after turning the heating on, the temperature in the RUB has hit 88.2F and is at 55% humidity ( after the spray ), though I can never be sure when the temperature drops below 88F while we are all sleeping and I just want to know if my little snake will be alright, I want him to be happy. I know I am probably overthinking this but I really want him to be healthy, happy, and feeding.