Residents and objectors living near Willingdon Golf Course have been told Vodafone has submitted an appeal to the June refusal of both a pole mast and a tree mast.
The company had hoped one of the two third-generation phone masts would be approved by Eastbourne Borough Council but both were refused.
The appeal refers to the tree mast.
Neighbours, some suffering from cancer and many fearing unproven health risks of living near a mast, had written hundreds of letters of objection to the proposals for the Area of Outstanding Natural Beauty earlier this year.
Some now plan to write to the planning inspectorate in Bristol and a petition is being signed, campaigner Naomi Markwick said.
A council spokesman said of the appeal, "It will be dealt with by written representations and the council has until October 24 to submit a statement to the Planning Inspectorate."
It is understood the Tally Ho pub, Church Street, is considering having a phone mast situated on its roof.
Eastbourne Borough Council said it had not received an application for a phone mast on the Tally Ho but an approach had been made by one of the mobile phone operators without any details.
A spokesman said, "They were advised to submit details but to date no application and no details have been put forward."