I noticed this same issue twice now.
With mode off, and on circulate, both times I set the “circulate” to “auto” and after like an hour or so, I realized the fan was still running (like it was just “on”), even though the tsat mode was in OFF. The only way I was able to get it to turn off and go back to Auto, was to set it to “manual” on the 2gig panel, let it run for a short while, then set it back to ‘auto’.
Both times, circulate was actively operating the fan blower when I switched it to ‘auto’. So it is like it never got the off command from ADC.
Strange because the circulate settings should be local.