I don’t really think Reg 87(1) applies here. You presumably received a claim in Jan 10 with a request that it be backdated to Nov 09. You decide there is no good cause for a late claim and award benefit from the date the claim was made.
Appeal says he does not agree with your decision and then asks if you will go back to Dec 09 if not all the way to Nov 09.
As long as the appeal has come in within one month of the original decision he is asking you to revise the decision. The dispute can only be over whether or not he has continuous good cause for a late claim. He *may* be able to show good cause for some or all of the period for which he is seeking benefit. As part of the appeal process you have to reconsider your original decision based on whatever additional info he has provided. That may lead you to revise the original decision for some or all of the period under dispute or to confirm your original decision that there is no entitlement to backdating.
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