Entitlement to Care's Allowance

Hello, I wonder if there is anyone out there who has been in a similar position to me and could advise me re claiming Carer's Allowance on an ad hoc basis.

My son, who was diagnosed with autism as a small child, had been in receipt of Disability Living Allowance for many years and was recently awarded Personal Independence Payment following a Mandatory Reconsideration. During the process of being transferred from DLA to PIP, I became his appointee, so that I may deal with correspondence regarding his claim and I am very grateful for the useful guides on your site which helped me to word my letters to the DWP. I have one query, however, on which I hope someone may be able to advise me, as phone calls to the DWP have been contradictory.

For the past three years, my son has been at university, living in Halls of Residence (in effect, sheltered accommodation) with extra support provided by the National Autistic Society, but I have been able to claim Carer's Allowance for the time he spends at home. We collected him from Uni for the Christmas holiday (three weeks), but he had been at home for only a few days when his DLA ended. (I'd already received a letter telling me my entitlement to Carer's Allowance would cease on the same date.) I was advised (during a phone call) by someone from the Carer's Allowance Unit that I would be entitled to claim for the time he had already spent at home and she sent me a form which I returned. This lady (who sounded as though she knew what she was talking about) also advised me that if my son's claim to PIP was successful at Mandatory Reconsideration, my entitlement to Carer's Allowance could also be reinstated and back-dated to the same date. However, when I received the Mandatory Reconsideration Notice and rang the Carer's Allowance Unit to request this, the man I spoke to said he did not know if this was possible, but that my claim for the first few days of my son's stay at home was "with the decision makers now." In my experience, they always say that, and then you hear from them a few days later with a new claim form, but this time, I have heard nothing, despite writing a letter explaining all this (in a similar way to the way I've explained it all to you, but with dates included) and sending it by "Signed For" post, so I know they received it.

My question is - does anyone know whether the first lady I spoke to is correct? Or is the only alternative to make a new claim? If so, could I do this when my son returns home for the Easter holiday or do I need to wait until he returns home from Uni for good? (Probably in the summer.)

Thank you.