Is possible to downgrade Sangoma S505 Firmware using EPM or the phone GUI? I recently purchased a batch of S505 phones and they came with Firmware 220.127.116.11 and that version is no even listed on my EPM Firmware Management (All Modules are Updated) neither on the Sangoma Firmware releases wiki (Last version 18.104.22.168). I already tried rolling back to a previews version 22.214.171.124 through the phone GUI and it wont take it and I also tried using EMP and no results phone is stuck with 126.96.36.199. The problem is that phone keeps rebooting over and over every 20 or 30 seconds when I try to provision and registration fails.
Any ideas how to rollback the firmware?