There are a number of threads regarding Flight Passes so this may not be the best fit, but I'm diving in with my question!

Has anybody found a way to force a layover when selecting a multi-segment option for using a FP credit? For example, if I want to fly YVR to YOW, but rather than having a 2 hour layover at YYZ...what if I want it to be 24 hours?

I have had some success in the past with calling in and providing the agent the segments I want. It can take them some time, but they can often figure it out. Be aware however, that the use of a credit has to comply with the connection rules. I don't believe a 24 hour layover is considered a valid connection and AC won't allow it. It is only allowed if it is the only legitimate option to get you where you want to go. You may be able to swing a 12 hour layover, but 24 hours is likely not valid, especially on a route such as YOW-YVR.

You're never going to get a 24 hour option if there's a 2 hour option.

In normal times, 4 hours would be the limit.

I definitely appreciate this, and I have certainly experienced the normal times :-) I guess my question was more whether anybody had found a hack. FlyBoi's suggestion is a good one; I recall doing that years ago.

That might work to get a 3 hour instead of a 1 hour.

It's not going to get you 24 instead of 2 on a North American FP.

I've forced a 23 hour connection or so from LAS - YYZ (stop) - YOW before COVID. Something like land in YYZ at 8pm and fly out at 7pm the next day.

I booked the connecting flights and called in and asked for a change right after I booked. Not sure if it's allowed or not but I did not get any pushback from the agent.

You can do that as a SDC, but otherwise it's not allowed.