Tracking bug is
https://crbug.com/500097773.
The job-scheduler behind the CQ is having trouble assigning tasks to machines. This means builds on CQ attempts will be pending indefinitely until things are resolved.
We've escalated this to the team that owns the scheduling service. However, given the late hours, this might not be resolved until early EST (UTC-5) Tuesday. Expect little to no CL submission until then.
Apologies for the disruption. If a CL needs submission ASAP, you can consider bypassing the CQ altogether via the 3-dot menu. But please only do so if absolutely necessary.
Thanks for your patience.