According to thesupported platform matrix page, it says that my airrouters, bullets and nanostation m9s are AREDN Stable, but, NOT recommended for new deployments.  Might be low memory or non MIMO.  I was running version 3.20.1.0 and figured for a long time I might not be able to run 3.22.1.0 on any of these.
Had tried to upgrade on one of the airrouters, but it wouldn't di it.  Found the reason, wrong version of the firmware, and it seems the old FW is smart enough to reject the wrong FW.  Anyway, I figured out which was the correct FW version (found on the administration page it tells what your node's HW version is "hardware type: (ar71xx/generic) ubnt (bullet-m)" (this is one of my nanostation 900MHz nodes) and you should pick the FW with this in its name).  DUH!  The upgrades worked once I figured this out...  My bullet says "hardware type: (ath79/generic) ubnt (bullet-m)",  My airrouters "hardware type: (ath79/generic) ubnt (airrouter)"  This helped me tell a Bullet XM from a XW and select the correct FW.

I was a tunnel client for some time (two tunnels, but I have two completely separate node networks so they don't cross connect, as per request of the respective admins) but they went dead.  Maybe my not upgrading caused me to be dumped?  Sent requests to be reconnected now that I upgraded but that was just last night so I have to give them some time to respond. 

Maybe factory to AREDN 3.22.0.1 packages won't fit in the devices' memory?  The sysupgrades did.