I dearly love schedules and routines. The rhythms are grounding and they anchor me a bit to this 'time' thing that everyone else seems to understand. When schedules get altered or routines get interrupted, I get confused and lost, and it takes far too much effort to find my place. I've walked out of more than one shower without rinsing my hair because traveling changed my morning.
When I was a child they insisted that allowing us our routines was somehow bad--and yet they talk about how establishing routines for things like bedtime is a good thing. This doesn't make sense for me, though I think the thinking behind the former was "you can't run on routines when you grow up".
Running on routines is exactly what I do. I have a set morning routine, a set bed routine, and several interchangeable day routines depending on what is going on that day. The week has the same rhythm. If the week doesn't have the same rhythm I get extremely tired and cranky. Sleep 15 hours at a stretch tired. It's not a good thing.
Since there are times I know my schedule is going to change, I can work with that. I write up my weekly schedule & post it on my wall 3 weeks before the change actually happens,right next to the current schedule. When it's possible to ease into it, even using a placeholder activity in place of usual down time, I do that. If I can make the same active hours in the transition, I can transition the activities more easily than trying to do it all cold. Downscaling is harder, but it's also ok to sleep for 15 hours when my schedule drops off, or I can fill time with things like "taking the cat for a walk" (no, really). It's also much harder to forget what happens in a day if I've been looking at it for weeks.
If I need to change a part of my daily routine, like my morning routine, it's a bit more difficult. I actually do have about 5 morning routines worked out now, but it took many years. If I need to do a new one, I write everything out and follow it step by step. Again, I start using the new one before I need to, even if it's for a short term situation. Especially for a short term situation, since if I'm traveling I need to be 'on' the whole time and will also be dealing with a bit of jet lag or con crud. It's still a bit jarring, but at least there's no "what comes after shampoo?" confusion.
I also really hate environmental change. Loathe. Despise. I hate moving and I hate when everything in the room moves and I hate when the grocery store changes where things are.
Unlike with schedules, I have absolutely zero control over most of these things! I almost never change my environment, except adding or subtracting a thing or 2 very gradually, but sometimes I'll go into work and everything will be wrong and my boss forgot to warn me and I start hyperventilating because it all changed! NOOOOO!
It's not reasonable for me to demand the inventory people at the store move things back in violation of their job, nor can I demand that work be put back how it belongs-and often, objectively, it's a better set up. I can, however, reset my mind so I can function.
I do that by going outside and taking a lap around the building. Or walking to get a snack. Something that takes long enough that I can calm down, slow my breathing, acclimate, but not so long that my old internal map of the place totally overrides the mind snapshot of the new layout. I'll still feel off for the first while, but it's better.
Soooo yeah. I hate changes and love schedules.