During this time we will be landing the patches listed on this page: https://wiki.mozilla.org/ReleaseEngineering:BuildbotMasterChanges#Upcoming_changes One of these requires a full Buildbot master restart - so expect some spurious burning. We'll do our best to minimize it and get things green ASAP. If there is any reason why we shouldn't go ahead with this please e-mail release@mozilla.com.