@Kevin_Z  The previous (200731)  were downloaded from  https://www.tp-link.com/ae/support/download/tl-wr844n/#Firmware  (i've tested the 200413 in the past too)

My router says: Hardware ver1.0 EU  and ALL the firmwares i've tested are for EU Hardw ver1.0  

I want to go back to the 200731 because in the new 211011 the QoS does not work well, the network bandwidth speeds of the connected devices shows frozen (this fault occur also with the fw200413);  instead in the 200731,the bandwidth use values shows in "real time" (it refreshes every 1 second). 

That's why i would like to go back to v200731

The problem is that bandwidth use of the connected devices (numbers marked in green) does not show in "real time", it shows "frozen", don't vary according to the bandwidth use at the exact moment you check it,  they lasts 15 - 20 seconds to refresh... this problem occurs with ALL firmwares i've tested, except with the v200731...   

With the 200731 these numbers refreshes every 1 second and shows you the network use really in "real time" (I loved this feature!!!)  but now doesn't work well, thats why i NEED to go back to the 200731 firmware!!!

@Kevin_Z