Most of the time, the non-home provider in other countries see your device as roaming, and often automatically upload the "settings" or "configuration" file to you & install it, resulting in the change. Good move to plan ahead, that's what I try to do unless I've already stored & saved the unique settings already. Not all devices are capable or accept them and/or if they are locked down, and in some cases, it's hidden or not accessible to the user.