Hi Doug,
If I'm not wrong, you mentioned from your existing blog post right?
If yes, that was the correct behaviour, example : If you create a blog post using Tiny-MCE editor, so this blog post editor can't change to Easyblog - composer.
The reason why we do this behaviour is because if let say I using composer create a blog post and insert a lot of different block, after that I switch to another editor, so that editor do not how to render the composer block, so it will messed up the content styling format.