When I was initialising Ubuntu quantal, I found that it seemed to be taking a curiously long time to do anything in response to me pushing the button on DistroSeries:+initseries, which I did at 13:45 UTC (timestamps per my IRC client). After twenty minutes or so I asked on #launchpad-ops if anything was happening. At 14:19 UTC, William Grant discovered that soyuz/initializedistroseriesjob.log was saying:
2012-04-26 14:15:04 DEBUG Lockfile /var/lock/launchpad-jobcronscript.lock in use
This is a rather general lock filename, and it turns out that pofile_stats was holding the lock. William asked webops to disable this job temporarily, and then initializedistroseriesjob was able to proceed. However, it seems suboptimal for this to require operator intervention.
I ran into this again while initialising saucy. The same workaround worked.