its due to the system the drone uses to store the info on the SD card the higher the resolution you use to record video, the shorter the time between each segment ,if you use 1080p at 30 fps,then you will get close to 13 and a half minutes, but in 4k this will be dramatically reduced
Welcome to the forum.
Your stored clips will break as OMM said but it keeps recording till
you stop. Just add the clips together in post and you won’t know
it did.
Statistically most people won't watch a long video. If they are for your enjoyment make them as long as you want but don't expect many people to watch them if over about 1:30 mins.