This is probably not 100% accurate, but it's close (I think). And it's profile of the week (not month).
There's a committee of Admins with some input from Leaders who put together a rough schedule of who and when they would like to consider showcasing on various weeks. When they're able, they share a thread out on G2G of either who they're proposing or let people know that they're soliciting for profiles, in either case, people often jump on the thread and throw out profiles as suggestions that are then considered by the committee.
Once a profile has been selected, it is swapped (I think it's Monday morning, but don't quote me) from the old one to the new one, and within the database, special links are extended to allow everyone that's connected to the global tree to find their path to the profile of the week.
This is done weekly for typically one Notable and one WikiTree Leader/Coordinator/or other so that everyone can see how they connect up with him or her.
When the special links are removed, you can only get maybe 10 steps out of the regular connection links or a bit more of you're connected by blood, so if they're any further away than that, you won't be able to see your connection unless they become of profile of the week again.
At least I think this is a fairly decent description of what goes on. Hopefully this answered the question.
