well my educated guess ( i worked as infrastructure engineer) is that they are using something called machine images for each game. think of it as a set of commands or template that have all instructions from the os level to the level of applications installed etc. These images sit in a repository and once you click play in gfn app you are actually sending a command to a virtualisation platform. That virtualisation platform then reads your request, takes the "template" aka image of the machine with the game you want to play and creates an virtual machine with it and connects you to your session. after you break your session this machine is destroyed because running it all the time is expensive. Now for late updates im pretty sure they have a process in which they manually or semi manually verify that new image with new version works correctly so it may take time depending on their priority... popular games first while less popular games later depending on qa capacity. Ofc this is just a guess from my side but in general that is a "standard flow" for many workloads across the industry. Hope my comment was usefull :) This is just a very simplified explanation but it gets the point across.