I became ill in March but was only able to re-claim ESA in September because owing to the severity of the condition, I was too unwell to act any sooner. I have provided a sick note going back to March because the GP was aware of the position. The DWP is saying that ESA may only be backdated three months but I am wondering whether this is a hard and fast rule that applies to all situations or whether there is any flexibility or a discretionary element?