I had no problem with my reservation number--however I have 2 contracts(2 use years, same resort) and used points from both to book my vacation-I received one confirmation letter with one reservation number for our one bedroom at the BWV.
I am not changing resorts, nor am I changing rooms.
One night is booked with the one small add on contract and the rest of the vacation is booked using my points from my main contract.
I called WDW DINE at 7 am 90 days out and was told that I could only book ADRs for that one night since I am checking out.
I explained that I was not checking out, and it was not really a split stay as I was not moving hotels, explained that it was a DVC points issue. He refused to book said it was nto possible for him to do it, the computer just would not allow it to go through. Riiiight

I asked for a supervisor-she was very nasty and literally would not even let me get a word in-my hsuabnd said he knew it wasn;t going well when all I was saying was Excuse me... excuse me, if I could just tell you...excuse me..excuse me... LOL!
Very frustrating!
I called back not 10 minutes later, deciding to let it go and just book that one night's ADR-got a different person, booked that one dinner and was about to thank her and hang up when she asked me for my next ADR-I said I can book the rest of the week? She said sure! Very friendly, very helpful, no problems whatsoever.