CJ
There is quite a difference between the criteria for Lower Rate Care and Middle Rate Care so it is not entirely surprising that an assessment is required, I am afraid that this is at the discretion of ATOS and cannot be challenged.
It is unlikely to be reflective of the quality of your submission or whether you meet the criteria, there has been considerable pressure, even with DLA coming to an end, for claims to be fully re-assessed to ensure that awards are made properly.
The following will give you some idea of what will happen at the appointment
DLA medical examination Good luck
Gordon