Originally Posted by phltraveler

As someone that works in IT, I have doubts on all three fronts.

1. IT integration isn't simple and there wasn't a true outage of any of Marriott.com that I could see. Bits and pieces went up and down from a public perspective, but from a GDS/backend central reservation system, it isn't completely clear. Between reports on FT of status not matching expected and the travel blogs (in both directions - seeing higher or lower status than expected), it's very likely that not all batched information loads/transformations have fully run yet and that all the data is transitioned.
   It's not incredibly surprising that in an IT merger of a complex custom reservation system with high uptime requirements and a merger of two giant chains that there would be IT issues - for example, people who used the same email and same password for both their SPG and Marriott accounts specifically have reported issues on being able to log into one of the accounts, whereas those who used different emails/same password or same email/different passwords have no issues.
   The display issue on the website could be a technical bug as easily as it could be a process in the merger that hasn't run yet to update that status in the my account page (or a combo of multiple technical factors).
2. The members.marriott.com page was primarily created to update people on what the new rules in the new program would be and thus the lifetime criteria and the way it was written focused on the new ways to earn lifetime. The LTPP grandfather for existing MR LTP was a relatively small subset of it and a distraction for 98%+ of the elite population.
3. We know of existing areas in the T&C currently on Marriott.com that still are erroneous. For example, a reference to what benefits an ambassador provides being listed in section 5.8, and then section 5.8 not existing at all, or any section describing exactly what an ambassador does, suggests errors on the integration that are either technical or related to human factors (e.g. posting an old version of the T&Cs, or oversights in the released version of the 25,000+ word terms that need to be revised in the coming days).

Out of the two possibilities listed, I'm inclined to go with the other posters and say that it's more likely that members.marriott.com didn't explicitly quote the niche case of grandfathered status, that the T&C omission is unintentional, and that the display when logged onto marriott.com/the app is an oversight and seen as a lower priority issue versus taking reservations, being able to check people in, and their lifetime/current nights and points history being transitioned properly, etc.... versus Marriott inventing a named status of Lifetime Platinum Premier that doesn't convey any benefits over Platinum/Lifetime Platinum, which could be seen as deceptive and potential grounds for a lawsuit.