IMO (and everyone has an opinion) If 'someone' has so much claimed, then I would expect them to have other active crew members and as such negate the 'I'm on holiday' argument.
I think 3 days is more than sufficient and having sleepers contest claims definately shouldn't be a thing. If none of your company has at least logged in within a 3 day period to 'refresh' your claims then I would not class you as an active company and thus subject to the loss of an area.
I only agree with this for PvE mind you.