Howdy Justin 
My guess is that do release upgrade would fail anyway cause you don’t have enough space.
Not sure what the exact number is but I just upgraded a much newer version of ubuntu and I needed to free a huge amount of space for it to let me through.
Stuff is all in Docker so risk is not super high, you can always just copy some folders onto a clean install and start from scratch if needed.
22.04 is the latest LTS, you are many versions behind.