That is a bad sign. It means that your PU coating is perishing
You could try to contact MSR via the shop that sold you the tent but generally that is not covered by warranty.
From Sierra Design : (tent care)
hand wash your tent in a mild, non detergent soap and water solution. Down Soap works well. (pure soap is the same thing)
Next...
Prepare the following solution after washing the tent as previously instructed: 1 cup of salt, 1 cup lemon juice (concentrated) and 1 gallon hot water. Rub the solution into visible mildew. Set up the tent with the affected areas facing the sun. Allow to dry. Once dry, remove all peeling coating. Apply a coat of McNett Tent Sure to the areas where the coating has peeled. This will help restore water repellency. (For more information on McNett Mirazyme and McNett Tentsure visit
http://www.mcnett.com)
So a lot of work but no sure outcome.
Franco