The Torygraph are today doom-mongering by saying the fare on the 840 will go from £4 to £25. The detail in the article says it might, and such a large change isn't likely to happen soon, but that doesn't stop their headline writers of course! Sorry I can't link, it's behind a paywall. (Although accessible if you disable Javascript)
There is also an interesting
thread on Twitter from Dan Neidle about ways to raise tax, which includes the observation that adding £5 to VED would raise around £200m a year. He says that this is unlikely to happen as it will affect the 'working people' that Labour don't want to impact, however it seems to me that adding a tenner would more than pay for the bus fare cap, thus allowing them to say that working people can choose the bus instead so won't be affected.