OP, I worked in Camera Enforcement until recently (in England not Wales though).
If it is a fixed camera she will probably have been pinged every time she went over a certain speed (not necessarily immediately over 20mph though). If it's a mobile van it will only be on the days it was there (probably only one day). Contrary to what a previous poster said, the fixed camera will have been on the whole time, they are not turned on/off on certain days.
Your friend would be best advised to phone the Camera Enforcement team and explain the situation, they will be able to check whether she has been caught more than once - at least she will then know what she is dealing with rather than stressing unnecessarily.
If there are less than 5 offences (assuming she currently has a clean licence) she should be offered a speed awareness course for one, and take 3 points and a £100 fine for the other 3 offences. This would put her on 9 points and her licence would still be valid.
If there are 5 or more offences (or she already has points on her licence or has done a speed awareness) she should request a court hearing, and explain the situation to the magistrates.
I would not advise trying to delay the process or employing specialist solicitors. All this does is piss people off, and in a situation where you will end up in court anyway it's better to have been pleasant and apologetic along the way. Don't give the prosecutor a reason to want to punish you!
Finally, it's probably going to be expensive, and yes she may get quite a few points, but it is possible to keep your licence even with more than 12 points, especially if the magistrate is sympathetic. The magistrate is more likely to be sympathetic if you are polite, apologetic and non-confrontational.