Most of my items are FBM and sub £10. I currently sell with freepost.

I have been thinking of reducing sell price by £2 and having a £1.99 charge. Amazon say the following:

*Free Shipping can lead to sales uplift by 12.4% on average (*based on a 2020 study comparing free shipping offers to paid shipping offers with the same total price (item price + shipping fee) as the free shipping offers. Excludes any additional benefits from a lower landed price. The study included UK/DE/FR/IT/ES locales. Specific ASIN uplift may vary).

Has anyone done the same and moved away from free shipping and seen benefits?