I started using it from the day I had existing marks! At first, I thought the spots wouldn't fade, and since they were pretty old, I honestly didn't have high hopes. But after consistently applying it, by the 6th day, I compared it to my previous photos and I was surprised to see they had faded more than I expected! Even though it's my first time using this product, I'm seeing results, so I think I'll keep using it :)
As I age, the marks don't disappear as quickly anymore, so this was exactly the product I needed. If you have similar concerns, I definitely recommend trying it out.