Addison Lee means to subvert the deterrent effect of Fixed Penalty Notices (FPNs) by paying them on behalf of its drivers.
But FPNs are not fines. They are an administratively cheap way to punish people who would prefer to pay rather than be prosecuted.
Key point: no one is entitled to an FPN as an alternative to prosecution.
If TfL is willing to stand up to Addison Lee on this, it should ask the Met to prosecute every AL driver caught in a bus lane, leading to criminal convictions and eventual removals of licences. That should restore the deterrent effect.