I have been able to allocate the Jan 16 increase (But during the Optimisation cycle the system (SAP) will run and I will more than likely have to go back in and reallocate because of the UD not being placed in prior to the snapshot etc, this is one reason I am kicking back on C2S changes)
For the volumes Fen onwards I cannot allocate the C2S, the system will run and on the 30th of September another snapshot will occur with another month allocated to C2S and more likely than not your volume will be allocated.