I have a friend that has asked me to help her band a billy and she said that he is 22 weeks old... is that too old to band? I’m pretty sure it’s a Pygmy or Nigerian dwarf, not sure if that makes a difference.
You won’t know until you try to put them on. At 5 1/2 months old it could go either way. I like to use a California bander on older kids & bucks. The whole thing is off in a week or less instead of a month or longer with the little green bands. Just make sure they’ve had their tetanus shot.