The mini 4 pro stitches panorama images immediately after the photos are taken.  During this time no control inputs are permitted.
Is there a way to defer the stitching process, say after the drone has landed?  If not this is something DJI's software engineers should consider.
PS I did look in the manual first.
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I think there is no automatic "trigger" to do this after landing....
...  so they do it immediately when the pictures are available, because at that moment the photographing process is completed.  
But I think the same as you!  
It's impossible to carry out such activities in mid-air if it would be necessary to control the drone manually...!!!   

Hmmm. Last time I was creating a panorama with the M4P I dared to continue the flight while processing was at around 85% and it was possible. I need to make another test in regards of that next time.

It would be beneficial. Just recently also, I've discovered a glitch with Panoramas, and wonder if it's just my drone or what. If I try to manually change the Ev setting before a 360Pano, from the default setting selected by the drone, it takes just two shots and then freezes on a shot of the sky.
Tried this three times, and only when I left the Ev at the default setting would the full pano be shot.

Interesting. I never tried stitching in the app, but if it works like that, it's a big no for me.