Upgrade Firmware Version 1.255 Ubnt -free- Download !!better!! -

Yes and no. Ubiquiti allows downgrading, but once you flash 1.255, the bootloader updates to v2.6. Some very old firmware (pre-2018) may not be compatible. Always keep a backup.

to the device's web interface (typically 192.168.1.20 ). Navigate to the System tab. Upgrade Firmware Version 1.255 Ubnt -FREE- Download

https://dl.ubnt.com/firmwares/airmax-m/v8.7.5/airmax-m-v8.7.5.50258.bin Yes and no