If the time between AccuRev SCM polls is less than the project's "Quiet Period", then the project will get stuck waiting for the "quiet period" to elapse and never start building.
e.g. "SCM polling" every 5 minutes and a "quiet time" of 15 minutes.

I have a project stored in AccuRev with the SCM polling interval set to "* * * * *", i.e. to poll every minute.
In an attempt to workaround JENKINS-8273, I tried setting the "quiet period" to a 90 seconds in order to ensure that two consecutive "changes found" poll results would only result in one build (which is, after all, the whole point behind the "quiet period").

What I found instead was that, after doing an AccuRev "promote" to trigger a change, the AccuRev plugin (correctly) detected the change and a build was queued with a "quiet time" of 90 seconds (as expected).
About 1 minute later (when the "quiet time" had dropped to about 30 seconds remaining), AccuRev polled the stream again (as expected).
However, even though no further changes had been promoted in the meantime, the "quiet time" was reset back to 90 seconds, seemingly as if new (fresh) changes had been found (there were no new changes, it was simply finding the original "promote" operation, i.e. nothing new).

What I expected to happen is that the lack of new (fresh) promotes would mean that the "quiet time" would steadily count down to 0 and the build would then start. What actually happened is that the "quiet time" never dropped much below 30 seconds, as it was reset every time a new SCM poll happened.