They got back to me, although it was well outside of the four hour window, and informed me that I would have no problem simply upgrading the account. However, I would not be eligible for the enrollment bonus.

I replied and questioned this. I told them that I am a very loyal Chase / Marriott customer, and would be incurring an increase in the annual fee for this new card. I also mentioned that fact that I recieve mailers several times a month marketing this bonus to me, and would find it dissapointing if they could not honor the literature that is sent so often.

We will see... and of course I will let you guys know.