I have been a Chase/Marriott Rwards card holder for several years, but I have the "regular" card.... I just sent them a secure message a few moments ago asking about "upgrading" to the Premier card, and also asked if I would qualify for the bonus that the send me in the mail often (50,000 and 70,000).

Personally, Im not interested in having too many cards, so my hope is that they will simply "upgrade" me without having to create a new account.

Will let you know their response.