I just got fed up waiting and waiting for this to fix itself. I have had 4g dropping nonstop almost all day long with full bars for the past month. Before that, everything was working great. I don't know what Verizon did, but it does not play nice with many Thunderbolts out there.
So I started messing around with the modem settings by using ##778# to see if anything would help with the problem. I figured it was a longshot, but it paid off. Since doing that, I have not had a single drop for two days now. The only two settings I changed were preferred settings and preferred settings(9k) both to automatic. Now 4g works like it used to.
However, this did cause my bars to no longer work correctly (phone always shows no bars now) and the time is always way off. I fixed the time by turning off automatic settings and manually entered my region. I have no idea why this fixed my 4g data problems, but i will take non functioning bars over no data at all.
Anyway, thought i would post this for anyone else plagued with 4g dropping over and over with their Thunderbolt.
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