UA short haul domestic with F only, no J?
 

Just made a larger booking in Business that involves a short haul UA domestic flight. No J was available so took the Y and was planning to watch to see if space opened up. However in looking at this segment it appears on the UA site that space only shows as Economy & First, not Business.
If space *does* open up under First Saver am I out of luck getting that on an Aeroplan J booking even though there is no named Business class on that route (and it's not 'real' F anyway)?
(Searched around as I expected to see this asked before but couldn't find it - sorry if I missed it)

Non issue. UA domestic "first" costs Aeroplan business points.

If you find that a seat opens on an Aeroplan search, you can call and change to UA first for free. (note Aeroplan bookable inventory does NOT always correlate to UA Saver Business...it has to actually show on Aeroplan site.)

You didn't ask this but just as an FYI, you will not be waitlisted or otherwise upgrade eligible at the airport or at checkin.

What Air Canada sells and calls a North American Business class seat, is equivalent to what the US airlines sell as First Class. Generally speaking the AC Business product is nicer than the US First product, however there are exceptions.

"First" is coded I
no issues

But even if it opens up, it will first go to any waitlisted UA award redeemers, so it's unlikely you 'll ever see it.