Apple releases statement revealing connectivity problems with the Apple Watch Series 3
According to the Wall Street Journal, Apple Watch models it has received that connect to AT&T and T-Mobile's cellular network have experienced dropped calls; the AT&T connected model also had problems reaching Siri. The Series 3 Apple Watch features a built-in LTE radio and an embedded eSIM card. With a cellular or Wi-Fi connection, it can make/take calls, activate Siri, send texts and connect to the internet without pairing with an iPhone, as previous variants were required to.
Another issue, which is actually by design, limits the battery life on the Series 3 Apple Watch to just one hour of 4G LTE talk time. If the cellular connected Series 3 pairs with an iPhone, talk time triples to three hours.