After migrating to Catalina mup didn’t work anymore. Running mup deploy I had an error "env: node: No such file or directory".
I found out that the problem was that I moved to zsh —as suggested by apple. Moving back to bash everything worked fine again.
BTW I really really hope that Tiny will put new energy to Meteor Up as well. The community needs to have an open-source tool to deploy apps to a self-hosted server. Today is much more convenient to use Digital Ocean than MDG Galaxy. It would be nice to have a paid service where you can deploy your app for $5 a month including MongoDB.