... following up from #77

#137 was deployed to @OpsBotPrime. Here we should catalog all real world occurrences of merge trains that happen over the next few days. We should do so by linking to this issue. Then we should go through each to double-check that everything happened as expected.

Any issues that are found should be created separately on Hoff's issue tracker and listed here from most critical to least critical:

• Restart all builds in the train after a failed promotion #170
• fix double rebase with single merge command #161

In addition to fixing the issues, we can also compute how much waiting time has been reduced.