Well, after complaining about this via the Apple website, I received an email today from AppleCare Agreement Administration, who actually *reduced* my warranty covered by 2 days (from 27th June 2012 to 25th June 2012) - [NB: 26th June 2012 was my purchase date, 28th June the shipping dates)! Grrr!
Anyway, I managed to get someone from Apple to call me back regarding this issue and explained again that, according to the UK Education Online Store, I am meant to receive 3 years of repair coverage. After some further discussion, where they agreed that this was what I should have received, I was told that my case has now been "escalated" and that it should be resolved in 3-5 business days and my support coverage updated online, but we will have to wait and see whether they do actually do this!