On the homepage, the description of the ‘FEATURED CONTENT - Free Content’ section says “Grab the latest October free content while you can”
These assets that 3dRaven linked are the same ‘Free for the Month’ that were on the UE Marketplace for October.
I don’t think there has ever been free elements that were only temporary. (Just Paid assets that were free for X month)
But what I think is missing is the ‘Permanently Free Collection’ - Basically that was assets that Epic paid the creators to make permanently free (as opposed to paying the creators to make their assets free for only 1 month)
This search query is the closest thing I can come up with that matches the previous ‘Permanently Free Collection’ tab:
https://www.fab.com/channels/unreal-engine?ui_filter_price=1&is_free=1&sort_by=createdAt