Would like to know when there are no work units left along with a parameter such as time elapsed since queue was empty. Currently there is a problem being discussed at
milkyway where fast computers complete too soon and ask too often so they get banned and end up not getting any work until a manual update is issued. Maybe the problem can be fixed at their end, no telling when though.
I would use the rule to issue a manual update and the rule would then be disabled and only re-enabled if more work actually arrived.
some projects go offline for maintenance but I have %shares set to allow other projects to start. The problem is fast systems getting "banned" and then needing an update to get more work.
Obviously this is a problem on the project server, but you might consider adding a rule to cover this.
[EDIT] Looks like there is a fix on the server side as discussed
HERE. Not the same fix as the topic suggests as one fix requires another as is usual.