I just combined my accounts, and it seemed to work without a problem. My reservations are all showing. My points total is correct. My lifetime nights were added together, so I have Lifetime Platinum. I'm short under 100 nights to achieve Lifetime Platinum Premier, that I understand is only possible until the end of this year. I can only get maybe 20 more nights this year. Too bad! One more year, and I probably would have made it.

I started the combination process from my Marriott login. I was a Starwood person and had that number memorized, but since they changed my SPG number, I decided to keep my long time Marriott Rewards number. The agent I talked to earlier said there would be no difference in benefits regardless of which number I picked. It is all one back end at the end of the day. I also tried to see if there were any downsides to combining, but I haven't found any. It is more convenient to have all my points, certificates, and account information in one place.