How to get NPCs to stay put while doing activities?

I’m talking here about the ‘acitivities’ menu you get from pressing ‘h’ on the ‘I want you to do something’ option when talking to allied NPCs.

Specifically, ‘please study from a book’ does not mean ‘follow me as soon as I’m ten spaces away’.

Is there any way to get my NPCs to remain at base studying while I’m off scavenging or clearing zombies?

a wild guess: the NPC is in a basement or at one of the top floors?

Yeah, I set them to reading in the second floor Foodplace hideout, and they abandon reading when I go down a Z level. Would they stay put if I left them on the first floor?

If so, then I guess I’ll have to work out how to protect them doing that.

Yes, it’s a bug, they were working fine for a while but something broke somewhere on the road to 0.F.