Does anyone have an experience of how long it takes for dissolving a Household account to take effect?

I want to UUA a booking for me and friends if availability pops up, but I'll need to dissolve my HHA to upgrade them (I don't want to add them). I don't need the HHA intact for any other reason in the next six months, but I don't really want to dissolve it unnecessarily, should space not appear for the UUA.

But I don't want to hold off and then find space opens up, only for it to take 3 days for the HHA to dissolve, and miss the chance!