I'm a MG1 on the KDF side. Finished all the romulan missions. Did the Darkness of the Dawn bit, but now it's not offering me the Cold Call mission on the Breen path. Hence, I can not progress any further. Talking to Ambassador Surah just yields him saying "All things in balance. All things in time".
This is the problem with the linear paths. If something breaks, the character can not progress.