I had a rejection that looked like this a few months ago, and I never really understood why it cleared in the end, so I am following this closely.
The one thing I would check before anything else is what the line is landing on underneath the exclusion. When ours started refusing, the exclusion was not the problem at all: the base heading had been changed under us and nobody told us; it simply began rejecting one day.
Has your base heading moved recently?
