The facility to select particular work types was dropped with the server upgrade a couple of months ago.
Now computers will get whatever is available for their OS.

The back off between work requests is 1 hour and a couple of minutes.
This is to slow down faulty computers from requesting more work to kill, too soon after the last time.

Otherwise you've got it about right.
Request work in the short time that some is available, and hope that everyone else is distracted just then.

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Too many Windows computers - too few researchers using a model type that has a Windows app.

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