Seems that with the stock kernel build 9/29, going to mobile networks in settings and selecting anything breaks LTE because there is no CDMA/LTE option (various combinations of CDMA and GSM 2G and 3G, but no mention of LTE in the selections).
However, I can fix it by using the LTE on/off app for HTC thunderbolt (works fine for droid 4).
Jelly Bean runs very well on the Droid 4 and memory usage is low also. Just tried stock kernel build 9/29 yesterday and the only issue I have is in-call audio routing over BT. Even A2DB works well over BT. I'd have to say for me, if the in-call audio routing over BT was fixed this would be a daily driver. This continues to be quite incredible, Thanks!
Flahsed the 10/2 build after wiping cache, stock browser FCs after google sign in
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