Upon further tinkering I believe I solved the problem but I don't understand why it occured in the first place.

On a fresh start of BIAB I loaded the song, unchecked freeze all tracks and then saved as in another folder other than where the majority of my songs are saved. I was then able to open it from that location and edit to my hearts content. I then saved the file under a new name in my song folder and I can now edit just fine.

I'm happy it's fixed but I don't understand why it happened in the first place. It seemed to be a corrupted song file but it didn't behave that way. I was able to edit it in realband without issue. Also once the error presented its self by opening the corrupted file all subsequent files that were opened suffered the same error. A clean computer restart would solve the issue of the other song files as long as I didn't open the corrupt one. Once I opened the corrupted file though it affected every song.

Hopefully the issue is resolved and doesn't return and I can breathe easier. I really thought I was gonna loose all my work on this song. I am perhaps considering keeping a separate folder with master saves in case this happens again just for some redundancy.