I am also in the UK and was told by my ADHD treatment team this week the following:
They will only keep prolonged contact with me while adjusting the medication type and level and that is all.
Once settled on one I would be referred back to the GP to keep an eye on the condition.
Any changes should be reported to the GP and they are to decide if to refer back to the clinic.
The only deviation from this is if the medications are causing sever side effects such as suicidal thoughts / depression / extreme weight loss to contact both the GP and the clinic immediately.
Have you told your GP / clinic team about how the meds are making you feel?