If there are other reasons for bringing a prosecution ie. working on Sec1 rifles/making rifles Sec1 illegally then that is the case that should be progressed.
It matters nought personally to me whether Lee is guilty of this particular demeanor or not. It appears not, as these charges were dropped. If they were so important they should have been progressed.
What is being claimed is another agenda from either a manufacturer or the police. Another fact is the rifles were sent to be examined by Ripley who retained them for some time, presumably outside of police control. Hardly the way to treat evidence.
What is important, or should be to any airgunner is that fact that the Tester decided he could adjust the rifles to get a result. Note, if this is accepted there is absolutely nothing that says when that adjustment has to stop or even what the adjustment can be. The Tester can make any rifle or pistol over powered as there are no restraints.
This means there is no safe way to set your rifles under the 12 FPE limit.