Hi
I presume, the (gift) settlement deed has the signatures of your father, your brother and yourself and the same is registered at SRO.
If it is a registered Settlement deed , then unilateral cancellation of settlement at SRO itself is void. So, all subsequent transactions (revocation deed, cancellation of revocation deed) are inconsequential in eyes of law.
Any which way, now that your father is intending to cancel the revocation deed, he should do so by way of executing a cancellation of revocation deed at Sub-Registrar office.
Once the cancellation of revocation deed is executed, you and your brother should apply for mutation of property in your name (i.e have municipal taxes, electricity, water bills should be in your name).
Hope this information is useful.