It depends how religiously you do the exercises they set FF, I could feel a marked difference within a couple of days of the first appointment. According to my GP it is the walking/running distances that causes it, so technically it will never really be cured, but Grosvenor took me from not being able to walk to the front door without crying to doing what I want with the minimum of discomfort. They went through all the exercises with me and then I did them again as soon as I got home so that I didnt look at the sheet the following day and think what????????
I did a 5k recently, first run since Jan 8th, the only thing that stopped me r*nning all the way was the heat.
Hope all goes well for you :o)