Essentially it's about using the available hardware and software in the most efficient manner. The cross-over from sieving to LLR testing is continuously moving and there isn't a single answer to your original question.
I would really appreciate if you could stop this really unfair (against other competitors) bunkering and apply the same rules as in the boinc challenges.
P.S.: I don't mind being last or in the middle with only one computer at hand.
I dont named it unfair, everybody has the same opportunity to do so
on the other hand: this challenge isnt managed serverside, so the boinc challenge rules about the workunit sent out at challenge time could not been handled by Roger or me. Any try in the past managing the pending work leads to much more confusion. Sorry for this.
Due to the four day expiry, essentially this means the challenge started on Monday 10th at 12:00 UTC and can be seen as a seven day challenge. :-)