"ThyssenKrupp's Marriott code TSN is for the German industrial conglomerate (steel, elevators, automotive). German industrial codes follow the European Marriott enforcement pattern: "In Europe, they tend to follow the rule by the book." ThyssenKrupp has significant European properties in Essen/Duisburg (HQ) and US operations in Birmingham AL, Pittsburgh PA, and Calvert AL (steel facilities). FlyerTalk notes German Marriott properties are among the most verification-active. No TSN-specific denial documented."

"I regularly stay at a renaissance once a month on our DTC rate and have done mobile check in but always end up at front desk. One time the front desk was like oh. We know you as you have been coming regularly, but I need to double check your id. I think it’s because someone shared it online and now it causes random checks for rest of us."

"I don't do mobile check-in if I'm wanting to upgrade. I check the app before I go in to see if any suites are available to book during the duration of my stay. If there is I just say "Would it be possible to get upgraded to an available suite with my platinum benefit?". Of course this is typically at the hotel that I stay in about once a month for 3 day at a time for work. The front desk pretty much knows me and know that I am fairly low maintenance."