Recently I shared about "Set reminder" and "Photo Stack" features coming to Google Photos. Another feature which I spotted in September was auto archiving albums which archive photos from your albums every 30 days. While I initially thought that this feature will apply to all albums but when I managed to enable the feature, things got more clear. Auto archiving is related to redesign of "Document" section which you see under the "Search" tab. 

So there are two things - "Documents" section redesign and "Auto Archive". The current document section is a grid pattern UI with 12 categories. While the new redesigned document section will have a list UI with only 9 categories. There are minor name changes in names of categories as well and some seems to appear completely new such as "Payment Methods". Payment Method will likely include pictures of your credit/debit cards and maybe other payments methods. Here is a look at the old and new UI in below screenshots.

Now let's talk about auto archive. Auto archiving seems to be part of the redesigned document section because the "Archive after 30 days" is only appearing for the categories under Document section. There is a new "Automatic album" tag inside each category indicating that photos are automatically added in each category. Auto archive feature is optional and seems to be disabled by deafult. Here are a few screenshots of the feature - 

These feature seems to be working fine for me but there is no words on the roll-out of the feature from Google. I can't provide flag for rooted users because there are more than 700+ encrypted flags for Google Photos and I am not sure which one is responsible for enabling of this feature.

For more such feature leaks you can follow me on twitter/x and join my telegram channel "Gapps Flags & Leaks" where I often share about new feature and flags as well.