I agree, I love red coach bags but they can be tricky to rehab. Before you do anything, you might consider taking the bag to a leather/shoe repair professional and asking for an opinion.
I've posted these pics before but they show a mahagony brown Patricia's Legacy 9951 that had a bad spot/damage on the front flap. I was going to try to repair it myself but the bag also had a tear so I took it to a cobbler that I had used in the past and trusted.
He was able to smooth the area and "spot stain" the leather and I thought that it came out great! Below are the before and after pics of the bad spot (before I restored the bag) and I was very glad that I had taken it to a professional; but remember, results may vary and red can be difficult! Good luck!
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