I'm sure somebody has gone over this already but I can't find it. Sorry if I'm repeating a question. I was wondering when it comes to spa treatments for our bags, are we suppose to bring them in regularly (once a year or once every two years etc.) regardless of the condition of the bag? What I mean is that if my Birkin looks good with no obvious signs of wear or damage, am I suppose to bring it in to maintain it, or should I bring it in only when it's showing signs of wear. TIA for the info.