I have issues with the previous post.
"Due to the wisdom of ..."
The District line between Earl's Court and Whitechapel is over 120 years old. The track needs replacing periodically. The best time to do this is at weekends. If this does not happen then the track will fall to pieces. You may argue that they could do it at night, but the power is only off for five hours overnight and you have to get all the equipment down there and then clear it all away again. Plus the workmen are always threatening strike action over permanent night shifts.
Now everyone knows that investment on the Underground has been in short supply over the years but it still annoys me when people moan about it. Either you want an efficient transport system or you don't. I do, and I'm prepared to forego the use of some lines at certain times if it means the infrastructure is upgraded. We've just had several months of the Charing Cross branch of the Northern line closed at weekends so the track can be replaced. They've now started on the Bank branch and the ride on the CHX branch is fantastic now. Well worth the inconvenience.
There have been suggestions that Ken Livingstone shut an entire line for weeks at a time simply to upgrade everything (track, signalling, stations) in one go but I don't think it goes down well with the commuters. Personally, I think it's a great idea. Can't see it happening sadly though.
I know it's a pain in the arse that you can't use the line nearer the surface to get to the gig but try to understand why.