The white spots are where some kind of liquid sat on the leather for way to long and made the leather soft at that spot. You my not be able to restore the tan color at those spots. I would use turtle wax brand leather cleaner and conditioner.
It sprays on easily and it's what I believe the best product on the market for normal cleaning and restoration. I have a 2001 Eddie Bauer 140,000 with tan leather and it looks great! Condition your seats at least every three months or as needed. Hope this helps.
Franco