I was hoping this could help me with a Symfony 2.8 to 3.4 upgrade, then later for a 3.4 to 4.x upgrade, but it seems that it only compares my Symfony version with the latest... which isn't helpful right now.
I'm thinking maybe there's a commit that will check Symfony version 3.4, but I'm not seeing any indication as to where.
Also, the README doesn't specify which OS and version its CLI commands are for. I'm on macOS Big Sur, and Apple has changed how things work significantly between versions to a surprising degree.