Slightly off-topic, but do be careful about reducing hours. It’s likely it will not just affect pay, but everything else in proportion - pension entitlement (including ill-health pension, if there is one), redundancy payments, should you ever be made redundant - everything.
Since diagnosis (2010) I was increasingly struggling with work, and often toyed with the idea of reducing my hours - say to a 3-day week - but thankfully never got round to it!
Last year, I was made redundant after 23 years (nothing to do with MS). Obviously, I couldn’t have foreseen that would happen. IF I’d switched to part-time working, the fact I’d been full-time for over 20 years previously would have counted for nothing, and my redundancy calculation would have been as if I’d always been part-time - i.e. just 3/5 of what I got.
I know money isn’t the only consideration, but it’s a big one, as it may affect not only your take-home pay at the moment, but what you’re entitled to for the rest of your life. So there’s more to look at than just: “Can I afford it now?”. You need to think about: “Could I afford it if my pension was reduced in proportion?”
The other aspect is that although employers often readily agree to reduce hours, it can be much harder if you change your mind, and want to go the other way. They are under no obligation to let you return to full-time hours, just because you used to do them. Look before you leap!