"More than half" of weekday trains will run during a 27-day rail strike in December, but the last services will be earlier than normal, operators say.
Rail, Maritime and Transport (RMT) union members at South Western Railway (SWR) will walk out in a long-running dispute over guards on trains.
The union has accused SWR of being "not interested in reaching a settlement".
SWR called the strike "unnecessary" because it had promised it would keep a guard on every train.
Following the release of the revised timetable, an SWR spokesman said: "We plan to run more than half of our normal Monday-Friday services and will provide longer trains in order to increase capacity wherever possible.
"Customers can expect a similar number of peak services to previous strikes. However, they should be aware that last services will be earlier than normal."
Strike days are as follows:
- From 00:01 GMT on Monday 2 December until 23:59 on Wednesday 11 December
- From 00:01 on Friday 13 December until 23:59 on Tuesday 24 December
- From 00:01 on Friday 27 December 2019 until 23:59 on 1 January
A revised timetable will also be in operation on 12 December, SWR said.
Weekday timetables for the 2 to 20 December are available online, and festive and weekend timetables are due to be published soon, SWR added.