In a brief follow up to this, I’ve taken some timing measurements and I’ve seen it take ~55 seconds to JOIN and about ~20 seconds (after that) to complete an CMSGHEX command. Is that normal?
I’ve also seen it take as little as ~16 seconds to JOIN and ~7 seconds to complete MSGHEX (unconfirmed send). I think if I can simply overcome the need to re-join after every power cycle the performance will be satisfactory for my application.