wordpress expert needed

Need a small customization of local shipping plugin of wo-commerce and need to be done right now. Task is There is the plugin called Local Pickup Plus u can see the plugin at [login to view URL] We need that plugin to be modified so that when someone chooses a drop point when they order the first time, that drop point is assigned to that user, and when they order in the future, that drop point will automatically be displayed for them, and not be allowed to be changed by the user. (as wp-admin we may need to change their drop points manually though occasionally) So to recap.... When someone places their first order, we need the plugin to record where they selected as drop point and then in future orders, that needs to be displayed on future orders, but they cannot change it. Need it done right away.