I attempted to download an install the 20H2 update yesterday on one of my laptops and it took 13 hours, from updates in settings it would download in about 2 hours and over the next 3 hours would install to the point of 73% and progress no further at which point a message popped up saying that something went wrong, try again, I did this 3 more times with no improvement, after going into the automatic help, even that did nothing to help so, the way I achieved downloading and installing it fully and correctly was to go on the Microsoft site, click on downloads and do it from there, that worked. In essence what this ‘update’ does is in fact completely reinstall W10 on your computer, from that point it took another 7 hours to complete. There were more than enough issues when W10 was first introduced, why, after all this time, can Microsoft still not get it right?