Many IPhone users woke up one hour earlier in Brazil today
Apparently, the IOS changed the phone time to DST, in last year (2017) the date to start DST in Brazil was october 15 (coincidence, no?).
Maybe this problem already occurred because the first change in DST rule, that changed the start date to november 4, because of the elections dates on Brazil.
If this assumption is correct, we had problems even with 10 months to update the DST rules.
It's a little sample of what can happen if the DST is changed again with only a few weeks to update all affected devices.
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