There is a bug when you set up your availability and clone it across days. Everytime you chose a day it adds time on the day your cloning. See Screenshot
I am able to reproduce this behavior on my end as well. I have just reached out to the product team regarding this and I will update you once I have more information.
I am able to reproduce this behavior on my end as well. I have just reached out to the product team regarding this and I will update you once I have more information.