I remember when the originals came out...and people being told to take extra care with it. Then the first problems started happening within days, the wrinkling underneath the straps on the papillon and the pochette.
Then...after about 3-4 weeks someone posted pictures about the stress marks on the bag (seriously...how much could you use a bag in that amount of time)!
Now we've got bubbling....
How often is 'Don't use this bag very often'? Once a year?
I really hope you get a response to your letter Claire...and if it is a form letter, then I would go one step higher until you get a satisfactory answer.
I fully believe that Louis Vuitton was not aware of the potential problems that might arise....HOWEVER, when complaints start rolling in, they should be resolving the complaints to the customer's satisfaction. NOT coming back with 'Oh, that's a natural process'. I'm sorry, bubbling is not a natural process on anything!!!