Reinhardt has an Epic Survival item called “Phoenix Protocol” with the following effect:
Phoenix Protocol
[Barrier Field] regenerates 50% faster and begins regenerating 50% sooner after being destroyed.
The wording would imply that the effect starts, when Barrier Field is completely destroyed and reaches 0 health, i.e. “destroyed”. However, currently it also activates when the barrier is simply damaged whenever you drop the barrier field to let it recharge.
I am not sure whether the problem is the Item description or the activation happening sooner than intended, but it feels great that it performs the way it currently does.