10 weeks for MR

I filled in my Sons PIP renewal form and both me and his Dad went along with him to the Face to Face. It was a joke. asking him to touch his toes etc.
He suffers from Paranoid schizophrenia for which he has deppo injections.
He is very severely affected and I detailed this in his application breaking it down in all the categories.
Moving on he scored 0 points not one. he had previously been on enhanced of both components.
I requested a MR and then got the mental health team to write a more detailed statement supporting his application.
I submitted this around 10 weeks ago.
fearing that nothing was happening or that the MR was negative I knew that we needed to ask for a tribunal and there would be a time limit.
I got Craig to ring last week they wont speak to me. he said that he did and that they said they had still not made a decision.
Because of Craig's condition he often gets things muddled up and does not deal with any admin at all.
I just think that this is a really long time for an MR and they usually turn them around really quickly. Do you think I am right to be worried.

They are currently sending out texts to confirm it can take up to ten weeks