How can I set more than screen time rule for my child?

Hello

I have screen time set up for my sons iPhone and iPad where he can share 4 hours a day between them but the devices are completely blocked from 8pm - 8am every day (to prevent him sneaking down at night etc!).

He now needs his phone at school but I want to block off 4-6pm as no device time so he can focus on homework.

how can I do that ?

if down time is 20:00 - 08:00 every day how can I add a second rule for 16:00-18:00 Monday to Friday ?

thank you