Based on the information posted here… It’s not the demand, it’s to make USCIS focus more on filings made between 2020-2021 (pandemic era) because people are noticing that newer filings tend to be adjudicated first. That’s why it also affected ROW (not just India and China). The retrogress will most likely to extend up to next year until they clear the COVID backlogs

Well that doesn't sound to be the accurate reason and is legally inappropriate to retrogress dates based on operational inefficiencies.

Because special exception is no more applicable from reasonable estimates

Retrogression could be mainly because of upgrades in the EB filings.

Let's urge USCIS to resume releasing the "EB 485 pending report" (btw they released for 10 years but stopped in 2018), which can tell us the number of people waiting in line before our PD and estimate the wait time. I filed FOIA request and commented on the USCIS data page (https://www.uscis.gov/tools/reports-and-studies/immigration-and-citizenship-data) many times to ask for this. The more people ask for this, the more likely USCIS will take this seriously and release it. (See more details here: https://uscis.gov/archive/questions-and-answers-pending-employment-based-form-i-485-inventory)