Whenever you join a server that has mods, if you join a server that introduces custom keybinds, it always resets the keybinds to the defaults.
The keybinds will only remain set to custom keybinds if you do not play another server in between, including official.
Once you change the server, the custom keybinds are lost forever, and you must painstakingly reset them all once again.
This report is not about modded content, it is about support that DayZ client provides modders for giving users the ability to examine and set keybinds.