Well, it's like that
Replication tries to propagate changes. If that fails, rep tries it again say after 1 sec. If it fails again, it tries after 2 sec.If it fails again, it tries after 4 sec and so on, until a treshold is reached (don't remember but after several tries)
Then the rep gives up, marks the job broken and never tries again. Here u should manually restart the process when everything is fine again

Cheers