ExpertFlyer vs CO.com Question
 

I'm looking at CO41 on 3/1 and CO649 on 3/6.
ExpertFlyer is showing
A9 D9 Z9 R7 Y9 H9 K9 M9 N9 B0 O9 V0 U9 Q0 I9 S0 W9 T0 X9 L0 on CO41
and
A9 D9 Z9 R0 Y9 H9 K9 M9 N9 B0 O9 V0 U9 Q0 I9 S0 W9 T0 X9 L0 on CO649.

However, searches on CO.com show no Z prices. Just A.
Thoughts on why this might be?

Not sure if it would work, but clear the cookies (from your browser)
for continental.com and try again. Some people have reported such
issues with CO web site in the past.

It may be that at this time CO does not have a corresponding Z fare in the EWRSFO market. Availability will show for all classes/buckets even though there may be no fare currently assigned to it.

Are there any Z fares loaded for this route pair? Restrictions? Maybe the Z requires a sat night or seven day return?

They do not. Seems like we answer this question about once a month.
The only published fares in the EWR-SFO market (I assume this is where CO 41/649 go, why is it so difficult to include that in the original post???) in March are: A, Y, H, K, M, N, O, U, and I. So the only first class fare is an "A" fare, for $639 o/w.

To the original poster: after you do your availability search on EF, then hit the "View fares for AAA to BBB on CO" button near the top of the page.

Thanks IJ - I did the legwork on the city pairs and you topped it off with the actual fare availabilty. OP is a relatively new poster (as am I, but a longtime "lurker") so I personally don't mind that it's a recurring question.