Thank you. Unfortunately in law, discrimination can only occur when a person is being treated at a detriment due to a protected characteristic such as race, gender, sexual orientation etc. as you have stated the reason is defending your rights, this would not fall under legal discrimination. If you are being penalised for enforcing your legal statutory rights then this would be actionable. However you would require to prove it. I would advise paying gate penalties "under duress" and make this clear, that way you will not lose your licences, then at that point, as you have made it clear you have done this under duress, you can have your legal position reviewed for intimating a claim.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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