I am guessing late June or early July...
And I'm in between undergrad and grad school right now, so my job is just a summer deal (ie, taking off is pretty simple). But I do want to be prepared to have a full day with the new MBP
Right now the 2011 Model is £859 education discount, and £849 refurb price.
Plus Education discount gets you 3 year applecare (well, 3 year applecare repair coverage, but only 1 year phone support) too.
It would definitely be worth paying what is going to be like at max £20 more for the brand new Mac on education discount.