Hello and welcome! Do please stick around fir the best information in BA that’s available.
The Rules are perfectly clear, and I have never had any problem in booking Flight+Hotel or Flight+Car. Howver, the current scenario is seriously weird, as you’ve noticed! Sadly I’ve not yet managed to get anyone at BA to take ownership of the problem … “It’s OK here” or “Contact our Sales people” … which completely ignores the fact that firstly I need to know where/when/how much!