Similar story here. Got mine back the other day, with just 3 days left on my 2 month extension. Luckily no further tests were required or I was temporarily screwed.
And yes, the new system takes longer than the old one. 28 days..? Try double that. Best of luck with it. The only positive is that it gets sent via email so if you're away from home or out of the country you can still receive it. As you say though, if you are required to do any further tests, you'll have to come back presumably.