Backdating SMI

Does anyone know if there’s a possibility of backdating a claim for Support for Mortgage Interest? The client in question is in the Support Group and suffers from severe anxiety, she requested an MI12 around 6 months ago but never completed it. I helped complete it last week and sent it off to the provider. Any chance the claim can be backdated to when the MI12 was requested? Or even to when ESA entitlement began? (Minus the waiting period).

This might be of some assistance.

http://www.rightsnet.org.uk/briefcase/summary/date-of-supersession-to-include-housing-costs-for-mortgage-interest-when-fo/

Perfect, thank you Ali