The order that the boxes are shown is a function of WP and not ACF. This order and the order set in ACF are not related in any way. Each user can reorder the groups and WP will remember that order. On top of this, each post type can have different values. Here’s an explanation of where these can be saved https://wordpress.stackexchange.com/questions/109112/how-does-wordpress-remember-metabox-positions. And to top this off, it will not be different for different posts. If the user drags the groups to reorder them on one page, they will be in that order on all pages. If they reorder them again, that will reorder them for all pages.
