How exactly does this work? Is the dispel check made when someone first enters the hallowed area? Or does it happen every round as long as they remain within? Does it target items, or only active spells? Is there an automatic attempt to counterspell against every spell cast in the area?
I have wondered the same thing. The conclusion that I came to was that dispel magic gets attempted on any creature that enters the area. But only once for each creature. Mostly because it would be excessive to have it continue to cast.
as the duration last a year. i read it as once per target that enter as set by the caster (if set for items or area or people etc). this might matter for stuff like how long does magic items are nulled if that happen.