This dispute WILL have an effect on the service, unlike the previous RMT station staff strikes as this time the drivers are involved. The LUL management may be able to sneak their own people into stations to keep them open, however they certainly can't get a non-qualified person to drive a train.
The dates of the two strikes announced so far are Tuesday 21st February and Thursday 2nd March.
I'm not sure of the exact details of the strikes yet, however it will probably be a case of the action being from 9pm to 9pm, therefore services will start winding down at 9pm on Monday 20th. I'll update you as soon as I know.
Before anyone posts comments slating me, I've mentioned before both here (and on Annie Mole's Blog comments) that I hate striking for anything other than safety issues, and I don't believe that the current dispute is about safety. Believe me, I'm as sick of strikes as anyone else.