Hello
Leather dries out because it loses moisture (water).
If the customer had been wiping the suite over with a damp cloth every week, especially where the sun was doing its worst this would have helped a great deal. The use of water based cleaners and protectors also would have slowed down the process. Customers are generally unaware of the maintenance that is required for leather and so they need this advice giving to them.
If the leather is aniline you will probably find there has also been a good deal of colour loss,(sometimes they can turn almost white) this can be fairly easily rectified with aniline restoration products. If the leather is a pigmented you may also find there has been some colour loss but it should not look as dramatic as on an aniline. The process to restore pigment colour however is more difficult than with anilines and will need a technician to carry out the process.
I hope this helps
If you want to talk this through please do not hesitate to ring me on 01423 881027.
Regards
Judy