The union at the centre of the Southern Railway dispute will table a new set of proposals during last ditch peace talks on Thursday.
Leaders of the Rail, Maritime and Transport union will meet officials from Southern and its owners Govia Thameslink Railway in another attempt to resolve the bitter row over changes to the role of conductors.
Union members are due to stage 14 days of strike action in the coming months, starting with a three-day walkout from next Tuesday.
Southern said it will run more trains than during previous strikes if next week's action goes ahead.
Almost all of the train operator's 156 stations will have either a train or bus service "of some description" if the action is not called off, and many routes will have trains running later in the day than on previous occasions.
Mick Cash, general secretary of the RMT, said: "We welcome the fact that the company have responded to the call for further talks and we will meet them with no pre-conditions and no arbitrary deadlines.
"RMT will be tabling a fresh set of proposals that address the wide range of issues at the heart of the dispute with the aim of progressing towards a negotiated agreement."
The company has set a deadline of 12 noon on Thursday for the union to accept a final offer before pressing ahead with the changes.
Notice letters will be served to conductors, terminating their contracts and inviting them to sign up to the new role of on-board supervisor.
Mr Cash said in a letter to Southern: "My union shares our members' concerns over your company's obvious briefings to the media over the past few days that you will be sacking them this week.
"This really is a disgraceful way to treat hard-working people - your staff - and cannot be left without complaint.
"To find out from the media that my members are in danger of losing their jobs is no way for a 21st century employer to treat its workforce or handle a lawful dispute."
Southern said there will still be a restricted service next week if the strike happens, with many routes having fewer trains, and some routes having no trains, but buses in the peak.
Angie Doll, Southern's passenger services director, said: "We very much hope that our talks will be productive and bring an end to this unnecessary dispute.
"But if next week's strike does go ahead, then we will be doing all we can to provide the best possible levels of service for our passengers, using every resource available to us."