I just wondered, for people who have been on the regimen for a long time and got clear from it, how long did it take for your red marks to fade?
"A long time" is a matter of perspective... On the "What To Expect" page it says you can get results in 5-8 weeks, it took me 9 weeks to start seeing great results and now I'm at 10 weeks and 6 days and only have 1 pimple. I still have old red marks though.
It can be really hard to tell how long it takes red marks to disappear, because I'd always get pimples in the same areas so I never knew if the red mark was from a pimple I just got rid of, or one that went away a few days ago. However I can report that on the left side of my face, which has been pimple-free for almost 2 weeks, there is only 1 noticeable red mark left. I use AHA+ as mositurizer every night and it's worked wonders for the scars.
So it can take as short as 5 weeks, to as long as 3 months (per What to Expect), to see satisfying results on acne, and red marks can take as little as a week or two to fade with regular (but gentle) chemical exfoliation.