Here is an interesting passage from the Congressional Research Service's invaluable The Constitution of the United States of America. ("Interesting" in this context, of course, means "supports my position.")
One of the more recurrent problems which Congress has had with [the Incompatibility] clause is the compatibility of congressional office with service as an officer of some military organization -- militia, reserves, and the like. Members have been unseated for accepting appointment to military office during their terms of congressional office, but there are apparently no instances in which a Member-elect has been excluded for this
reason. Because of the difficulty of successfully claiming standing, the issue has never been a litigatible matter.
Congressional Research Service, The Constitution of the United States of America, Analysis and Interpretation 135 (1996) (footnotes omitted) (emphasis added).
So we have a really interesting constitutional issue dealing with the interpretation of a provision that is hard to reach. The Lane case presents about the best possible claim for standing. If the Solicitor General seeks cert in this case, bet on a grant. The Solicitor General's certiorari success rate has historically been about 70%, compared to about 5% for everyone else. Rebecca Mae Salokar, The Solicitor General: The Politics of Law 25 (1992) (between 1959 and 1989, the Solicitor General was successful in obtaining plenary review 69.78% of the time, whereas private litigants were successful only 4.9% of the time).