All this seems really stressful. I mean, it makes it hard for any person to get into a rhythm, whether spectrum or not. And then, I'm assuming you may be working with a lot of new kids pretty much all the time?
Now, even with all this, you still want to assume success and plan for success. There's my method of 0,1,2,3 writing and under-writing, which also helps to build my skills.
That is, I don't get bogged down with a long writing session. I might be studying geology or art history or something else I find interesting, and on a piece of paper to the side I might write one, two, or three things, or zero things and that's okay, too. It's more a zen art of allowing something to happen rather than trying to force something to happen. And these things might be something I want to try in the future, or something I wish would have worked out differently.
So, if it feels right, you might tell them you're going to come back as soon as you get the doctor's okay?
I mean, assume success throughout even though there are some steps involved. And a good way to talk to your supervisor is an email with a follow up phone call the next day, but it's not the only good way.
And maybe some limits. For example, maybe at first not more than 30 hours a week when you first go back. And then, when you get back in the swing of it, back up to 40 a week, but still hard with this variable schedule.