After every RYR flight we log number of Free Gate Bag tags issued at the gate against the number of Free Gate Bags loaded/tags recorded by Dispatcher/Load Controller. We also have to log if any bags are offloaded by crew and how many checked in PAX there were at check-in closure.
From our latest instructions, any more than 140 PAX booked/checked in then we need to start placing cabin bags in the hold as Free Gate Bags. (Or 130 PAX on flights to/from Morocco). A second cabin bag is guaranteed onboard for first 90 PAX.
So 165 PAX checked in then we need at least 25 Free Gate Bags. There's no weight effect anyway of Free Gate Bags, they just have an effect on the trim on RYR loadsheets. Anything between 18 and 58 Free Gate Bags in Hold 2 for example is a trim effect of +0.1
With regards to why they stopped accepting FGBs at check-in/airport belt system....it doesn't mention a reason for stopping in the latest memo.