OK, this looks like an old bug.
It seems to stem from a change to the way the option parsing was done, it used to be that getopt didn't know that -m took a parameter and it was fixed up later, leaving the argc to be 2 (in the same way as if you hadn't said -m at all and specified a month + year).
This fix seems to do it, and I've tried a bunch of options. Note I also looked at the upstream FreeBSD code and that's changed a lot more and probably doesn't still have this problem.
OK, this looks like an old bug.
It seems to stem from a change to the way the option parsing was done, it used to be that getopt didn't know that -m took a parameter and it was fixed up later, leaving the argc to be 2 (in the same way as if you hadn't said -m at all and specified a month + year).
This fix seems to do it, and I've tried a bunch of options. Note I also looked at the upstream FreeBSD code and that's changed a lot more and probably doesn't still have this problem.
Dave