Occupational health assessment for reasonable adjustment

My partner has requested a reasonable adjustment at work to help him manage his ADHD. He has asked for a fixed work pattern rather than the varying shifts which are the norm at his workplace. He is currently working regular shifts and it has helped him immensely in terms of regular sleep patterns, eating habits and the general need for regular, consistent routines that are beneficial for an adhd brain. He will also be starting titration soon and will need regularity so that he can take meds at the same time each day.

His employer has only agreed this pattern on a temporary basis and has referred him to occupational health before it is made permanent. It is worth noting that his employer is not supportive and will only put this in place if they absolutely have to.

He has had his occasional health assessment today and the doctor has said that she will make the recommendation that he has the fixed working hours while he is going through titration and after this will return to the varying shift patterns.

I suspect she is approaching this from a place of ignorance and is treating it as a temporary need to adjust to medication and that once he is stable on meds he will be "fixed". Obviously this is not the case and we already know that even if the meds help, he will still have ADHD and have the same need for consistent routine in order to keep on top of the lifestyle factors which will help him to manage his ADHD.

We know that we can challenge the occ health report, but I believe that we can only challenge inaccuracies etc. We'll have a look at the report when he gets it and see if there's anything we can challenge in terms of it being a temporary rather than permanent need, but I suspect he will have to request another occ health referral when he's coming to the end of titration and be a lot more assertive in terms of this being an ongoing need for a reasonable adjustment. If possible I would accompany him to this next appointment to support and advocate for him.

Does anybody with a knowledge of employment law/the Equality Act have any other thoughts on this? He is finding the whole process incredibly stressful and it is having a detrimental impact on his mental health. He was hoping that after today's appointment he would be closer to getting this resolved but it now looks like the battle to having his needs met will drag on even longer.

I'm lucky enough to have a supportive employer who accepts what I ask for in terms of reasonable adjustments and puts them in place because they genuinely want me to be able to do my job without it making me ill, so it's utterly rage inducing to see the hoops they're making him jump through to access a fairly basic accommodation. I suspect they'd rather he just left, but other than his employer being a **** he enjoys his job and it pays fairly well.