Someone help us identify what this is.

My sons and I were outside playing and rockhounding. When we were getting on the trampoline they pointed out this large cloud that was shaped like half a riv cage or a palm leaf, to each their own. Normally they kind of tease me because I am the one pointing out things I think look strange but this time they both were twlling me to look at this. Im posting a link to yhe first 5 minutes of video but if you watch there are other clouds around that are blowing away pretty quickly and this one is clearly much higher up in the atmosphere yet it never moves never changes its shape just kind of hovers there. After about 5 minutes a grid of jet planes start to appear and seem to be blanketing the sky.

Any help is very appreciated, have a good day.