Who I have the same questioned this topic

I just got the Galaxy Note 3 and I am noticing the same issue.

I have my phone in LTE/CDMA mode.  When I got the phone it came in Global with roaming turned on.  At first I thought that was the reason, but it continued to happen.

I think Verizon really needs to explain why areas blanketed in 4G seem to mysteriously drop to 3G. 

I live in Avon, OH and we are solid 4G.