My mod adds a new buff to beacon that allows players to fly in survival while inside the beacon area.
But every 3 seconds this mod is removing the fly status if the player is in survival.

Mod: Big Extras
warn.txt

I would strongly suggest you start using this library instead. Not doing so will result in incompatibilities with every mod you mentioned regardless.

By adding this and doing some cleaning I was able to fix the problem.
I'm closing this issue because is no longer relevant.