Items/triggers removed from templates

[Noobz]

I have many hosts being monitored using a template with some triggers, when I remove a trigger from the applied template for whatever reason, will the trigger on the affected hosts disappear eventually? If so, when and and where is the setting to change this?

EDIT: Disregard this, I'm thinking of the setting in discovery rules"Keep lost resources period"
I vaguely recall seeing something regarding how long to keep orphaned data for or something like that and it was 30d from memory, but I can't find that setting now.

[Noobz]

I'm hoping I don't have to "unlink and clear" the template from every host - this would be a real pain as I assume we'd lose all the historical data?