New Releases of Gutenberg Breaking my Custom Blocka

I noticed it first with 4.5.1, after upgrading my Gutenberg version, all my custom blocks are broken in their existing placements, and they are not showing up in the block selection window on the editing screen. I didn’t see a place or resource in the update notes about specifics that might’ve changed with the Gutenberg api or packages, so I decided to wait until the next version, but now that 4.6 is out, I still have a bunch of borked blocks, so I have to use v4.1.1.

If something was deprecated, or has changed I’m just confused on where to go find that information.