In today's world, things like server maintenance and upgrades are normally painless processes that can be done without issues. Sometimes there might be downtime if it's an intensive update, but that's typically as extreme as it gets. Niantic, the makers of Pokemon GO have posted an alert that it will be performing server maintenance over a few days that could potentially interrupt players.
Niantic sent out a tweet from the company's Support Twitter account stating that it will be doing server
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