>That would be my ideal for how UBI would work: make sure people never have to chose between a bad job and starving or being on the street; but also make sure they have a clear path and opportunities to improve their situation and become more valuable to society.

I think this discounts the formative experience of the prior years. I would expect it helped by: 1. Motivating those guys to make themselves more valuable on the job market. 2. Giving those guys baseline discipline/reliability to get them to their next work and training milestones.

The military reserves is an interesting beast, but if you were in the active component before that, you probably ran into lots of guys needing similar training in basic reliability. UBI could be a strong disincentive away from those minimum-wage jobs, and the outlay described by grandparent is superior to a minimum-wage standard of living.