Scenes are associated with group numbers. Since I am moving the Insteon devices to OpenHAB, I decided to manually unlink/relink all the Insteon devices and start fresh, using Insteon Terminal to remove any orphan links (
https://groups.google.com/g/insteon-terminal/c/iGHrubKqKdE). I found two switches that were locked (
https://groups.google.com/g/insteon-terminal/c/eKlCgZih2Qc) and had to be factory reset.
The Insteon manual suggested that any schedules in the hub would disappear when devices were removed via the Insteon app. I do not know if removing the links via Insteon Terminal has the same effect, but my lights are now only controlled by OpenHAB.