Bannerman in party play

So we've tried using a banner stacking support for party play purposes, assuming the bannerman notable would be present on the carry and other members of the party, the wording on that notable doesn't say that only the user of the banners would benefit of those effects.
The current situation is that if the banner support has that allocated, the banners persist after leaving the banners' area, however if the other party members have it annointed or allocated, if they leave the area the effects of the banners are removed immediately.

If the case would stay like this, the wording of it should be updated to only the caster would benefit of these effects.