I've been having this same issue with my iPhone 11 Pro Max since beta 4 of iOS 14.
Very disheartened to hear that it's still not fixed in 14.2 GM.
My iPhone no longer maintains a reliable Bluetooth connection with either my Jabra Elite Active 75t earbuds or my Bose QC35II headset. And it's entirely unpredictable: they can work fine for 15 minutes and then disconnect/reconnect five times in the next five minutes.
Interesting to note that many people here seem to also have an Apple Watch. I'm going to try the suggestion of putting the watch in airplane mode.
melvynadam
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