I am trying to book a ticket EWR-IST-CEB. There is a technical stop in MNL along the IST-CEB leg (making it EWR-IST-MNL-CEB), but its only 85 min on the ground. When trying to book this though, it gives me an error that you cannot book a stop over on a one-way ticket. A ticket without the tag flight is able to be booked, so the stop in IST at 12hr 25min isnt the issue (less than 24 hours, so not a stopover).

Is the tag on flight somehow considered a stopover for award tickets? Im sending over points from a CC, so want to make sure it's all good before I commit the points.