OK, after a couple of days strategy suggested by @cezarL works like a charm:
- do everything in the morning
- do current day lessons around noon
- do custom study for apprentice 2 in the evening to jolt the memory for new items of the day
takes a bit more time in the morning (instead of scattering it throughout the day) but it’s less daunting and I have more or less single bigger session per day and I’m done with it 