EHM The Blue Line

Does anyone know the history of all these games?
I recall years ago finding the Eastside game, then it became something else (dont recall), then the FHM games by OOTP.
They all seem so similar that I am assuming there is a common thread.

Does anyone know the quick history?

Here you go: https://en.m.wikipedia.org/wiki/Eastside_Hockey_Manager

Eastside Hockey Manager is entirely unrelated to Franchise Hockey Manager.