A solution requiring no thought is just call approach per normal, and
switch to further freqs as instructed or to just "stay with me," as
happened to me once at big Milwaukee apt at 5AM, from 30 miles out to
all the way to shutdown.

Fred, I want to make the initial call on the proper frequency. When
I've
been on the ground preparing to taxi and I hear on the ATIS that
tower, ground, and clearance are combined on TowerFrequency, then my
initial call has been on the TowerFrequency. Likewise, when I'm on
the ground preparing to taxi, I've hear on the ATIS that all
frequencies are combined on TowerFrequency, then my initial call is
on TowerFrequency. This was the first time I was ever arriving and
heard on the ATIS that all frequencies are combined on
TowerFrequency an it seemed to me like that meant that my initial
call should have been on TowerFrequency.

I you happen to know the same guy has been working twr and ground,
after startup, wouldn't you still call on ground freq? Otherwise,
you're setting yourself up for embarrassment if 10 seconds prior, the
ground controller returned from the can, and both positions are back
to normal. Correct?

Hmmmm. I have no insight into who is working where. But if I listen
to the ATIS and it tells me to use a certain frequency, and I use some
other frequencey, then wouldn't that be setting myself up for
embarrassment (they might figure I neglected to listen to the ATIS).

Arden