Thanks to everyone who replied.
I agree with Leah that the UEL list doesn't seem too helpful. Both sides of the family concur that of two brothers, one stayed in the U.S. and fought in the Revolution while the other was a loyalist. A family researcher in Canada is the first person who told me the loyalist story, but now, of course, Wikitree is encouraging me to find sources, not just stories. Landon's father-in-law Albert Williams is on the UEL list--maybe--I mean, it doesn't list any information beyond a name, so there's no way for me to know if it's my ancestor or not. I'm not into hereditary organizations, although I could probably belong to quite a few, but just asking this question has given me useful information and perspectives about my probable loyalist and proven traitor ancestors. : )