I have not seen that Intuit/QBs has fixed this major BUG yet.  So DO go to Help and send in a Problem comment to them.  (This one ranks right up there with some of the other "they did what???" things they've done.)

I really don't know if it will work, but you might enter the Post Office's address in as the Physical Address, then in the next line add "Box xxxx"   If that doesn't work, try it without the "Box" in there, just the number.

Again... Speculation on my part, but I'd think the PO would figure out what you're doing.  But then again, it is the PO (regretfully not meant as a joke).