Keep in mind it's the overall average humidity over the first 18 days,The 'bator was at 48% humidity and 100* this morning. I did have to add a bit of water last night before I fell asleep though. I'm going to get a medicine syringe and some tubing this morning so I can add water without opening the lid.
so if it goes high or low for a day it won't be the end of the world.
Marking your air cells when candling can help you determine whether your target humidity is appropriate.