BEFORE YOU READ THIS REALISE THAT I SCR3W3D UP AND IT'S OLD INFORMATION! 
I found this on the 8AEF Facebook page:
They are grounded due to a problem with one of them at RAF Collage Cranwell. For safety reasons the fleet of tutors have been grounded until there is sufficient evidence that the problem will not effect any others.
Safety is the number one priority. This will then give them time to find the problem, if there is one, and resolve it without the chance of another incident.
No reason to doubt the source.
CPL Clott