I treat all my bags with respect and love! I store flaps uprigt in their dust bag, chains always inside! GST lays on the side; in the Mix tote lays on one side without further attention, it is currently my most frequently used bag.
But - accidents happen: one time I had the chain made HORRIBLE imprints on the outside of the flap of a lamb M/L black classic bag (it was not stored witth the chain inside the bag, but was laying on the face with the chain underneath it for longer time, wrapped in the dust bag and locked in the box! Oh horror!). It looked permanently damaged! I wouldn't believe until I witness by myself: all imprints disappeared by just rubbing gently the lamb leather with a moist cloth (no further conditioner). Lamb leather is not so sensitive as we all think! This flap looks like brand new again!
Moist cloth - you mean using water instead of leather conditioner? I wanted to learn how to treat my lamb jumbo too. Thanks!