This was suspected to be the case, but has proven wrong by many people's experiences. The .15 radio is the only radio that will easily pick up B26, eCSFB enabled or not. .17/.23 simply do not connect to band 26 like they should even when eCSFB is fully activated. Personally, I run .15 all the time because most of the B26 around me is eCSFB enabled. On the off chance I hit a new B26 tower I can always force 2G/3G to call/text.
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