Thanks to a report by a woman in Austin doing hawk-watch, who noticed the time of day she saw monarchs coming through--with a peak in numbers between 10 and 11 am--I broke my writing day today and went out to see if they were in evidence here at that hour.
That would be a yes. This plant had more than six on its many stems at one point. Also had monarchs in the creek woods, resting on twigs and leaves. More pictures later; I need to get my words finished.