it's highly unlikely given you have moved to an area with no coverage - had you contacted to sign up, were advised you'd have coverage and found you didn't have, then they would do it, but given the circumstances, it's highly unlikely (i used to work for one of the telcos and it was rare for them to let someone out of a contract for coverage related issues when the person had moved from good coverage to no coverage

however, if their coverage maps on the net say you should have coverage, you have more "oompf" to use to fight them as their systems say you should have coverage...