I had that message too for awhile a few days ago. It's from too many workunits errorring out or being aborted. It resets after 24 hours and starts getting new work again. It'll get one WU, when that one completes successfully, it'll ask for two, etc. and keeping doubling up to the max number of workunits allowed by the project, with each successful return. Everytime a workunit errors out or gets aborted, it cuts that by 1 again. At least in theory that's how it works...