Food related patterns would be pretty strong indicators for me as well, I think.

I only eat after 4pm (sometimes only from 6-10 or so) and people comment when I actually eat earlier than that, especially breakfast. I almost never use condiments or salt (I’m on a very low sodium diet and have been most of my life; I don’t use salt outside of baking, and that’s half salt). Give my dopple unsalted fries and you’ll know right away.

Drinks would work well for me as well - coffee made a very specific way, or room temp water, mostly (I actively dislike cold and hot water).