We recently had problems with our overdue "Suite".
Once the contract became overdue - and we were advised we had a couple more months to wait. I asked them for a suite of furniture to tide us over until it arrived - they delived this the next day.
When the suite did arrive 21 weeks later - when it came time to paying the remainder due - I asked them for free delivery - they agreed.
Point to note - if you do not ask, you do not receive!
I was at all times nice when asking, not to rub them up the wrong way.