I've noticed the price jumps too on a lot of profiles. I know a lot of the working girls do this at Christmas and other holiday periods to pull a few extra pounds in, but to me it's just daft as it usually has the reverse effect and just drives punters away. Personally, I avoid anyone asking for more than £130 an hour. I'm much more likely to have 2 punts at £60 for 30 minutes, than 1 punt for £90 for 30 minutes that some of these girls are asking for.
And don't get me started on the newbies that are asking for extortionate rates!!