summoning the herald

{quoted}

I think the decision to lock you out of your trinket while carrying the buff makes for an interesting decision point for the player/team. Perhaps it changes who you opt to take the buff (all your teammates can still use their trinkets). It might also partially influence the decision to use it, if you feel you need the trinket active back.

However, I could see a case for allowing players to self-cancel the channel without losing the buff (perhaps by pressing their trinket hotkey a second time).

you don't have the time to cancel once you call it you cannot react to do that