Quoting it word by word: " .....The JustLend team ... @officialjustlend

Answer:The JustLend team analyzed the USDD supply mining data and found that there was excessive use of circular loans and leverage. In order to maintain the stable and healthy development of USDD market and ensure the safety of investors' assets, JustLend decided to adjust the APY algorithm of JustLend USDD supply mining from 20:00 on May 29. The new APY will be calculated based on the investors' net supply, which is the total USDD supply minus the total USDD borrow. This means that the APY will now be applied to the whole supplied amount, not just the difference between the user's USDD supply and borrow. This adjustment is designed to ensure that USDD supply mining is done in a safe and responsible manner, and will help to maintain a stable and healthy USDD market.

They adjusted how USDD supply mining APY is calculated, not how it is applied. Your belief that USDD supply mining APY applies only to difference between user's USDD supply and borrow is simply a misunderstanding. It applies to whole supplied amount just as in cases of other assets with supply mining.