Ideas
I can’t find a specific post about it, but I sent a child to the camp getaway and the preset schedule changed randomly as I was playing. One minute it was “water activities” and next time I looked up it said “marbles”. Also the first day of camp it was only the campers there, the counsellors and directors didn’t show up, when one did, she didn’t cook or anything.
I’m on PC, pretty much every dlc except a couple, no mods or cc.
There is an option that it looks like you can't change after the getaway has been started. In the 3rd tab when you are having your sim plan the getaway in live mode, it asks for (idr what its called) like extra options.... elimination options like that. the window looks like modifying a holiday with the holiday activities. There is one called activity shuffle and it will change your activity randomly. maybe this was selected? of course you can't check once its been started but you can keep an eye out for it next time.
As far as the counselors not showing up, make sure that all roles are in every time slot that you created. I had a maid but didnt add her to one of the time slots and she didnt show up until the time slot she was added to.
Side note: if you're doing something like staff that you dont want to have to provide a bed for, dont put their role in the sleeping time slot. Hopefully they go home, well, sometimes they go home lol.