The offending lines of code:
https://github.com/lilypuree/UnEarthed/blob/1.18/Common/src/main/java/lilypuree/unearthed/block/RegolithGrassBlock.java#L48-L54

The set states above really wreaks havoc if your base was built a top bare regolith before this update was made and just converts any blocks back into air, including block entites like chests and stuff.

Not sure what the purpose or idea was behind the set block state above was but it should just be a simple fix of removing those set block above lines.