This issue has been present for quite some time but I can't see if it has been previously reported.

If you have more than one character that applies the same debuff, but for different duration, the most recent debuff will overwrite the current one, even if it is for fewer turns.

Example:

Horus has a chance to stun for 1 turn
Eternal Eddie has a chance to stun for 2 turns.

If EE stuns a target for two turns and then Horus gets a stun, the 1-turn stun overwrites the 2-turn stun.

This can also be done with one character such as Beast Eddie's fury, where each new fury results in a new application of a 4-turn doom, overwriting the previous counter.

Expected behaviour is that a debuff will not be overwritten by one with fewer turns, or one with a higher count if it is a decrementing type (eg, doom).