I should have read it more closely. It turns out they intend to cancel our policy because Himself doesn't have a license for the state in which we're insured, never mind that they haven't said a word to us in the past THREE YEARS that he's had a Colorado driver's license with a clean record (I don't drive here). The notice was dated three weeks after getting our payment for coverage through the end of the year.
We've already talked with his first shirt, who agrees with us, so tomorrow I expect to spend a lot of time on the phone with Progressive and then on to either base legal or hunting for new insurance if they can't be reasonable.
Does an auto insurance provider exist that's both affordable (for an E-3 family on one income) and doesn't pull stunts like this four months before we're guaranteed to be gone?