It's not a theory that what's kinda happening. I been had b26 enabled on my phone way before this update so I been seeing it. Some newly activated b26 sites don't get the ecsfb patch so if you connect to it the radio throws you off it because your phone won't be able to make calls while connected to that tower. It's completely random why some towers get the patch and some don't. That's all up to the vendors reasoning which is pretty unknown.
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