The approximate 100 sites are in places that cannot be upgraded. They are sites where the site owner will not allow it, the site Owner couldn't come to reasonable terms on the site lease negotation changes, or the site doesn't have a structure that can physically support the upgrades, or the site is planned to be decommissioned and replaced with a new site in the near vicinity, or the site cannot get backhaul fast enough to support LTE (most common in very remote Western U.S. locations).
This is a pretty rare thing, on average there is only one site per market that will not get Network Vision/LTE upgrades. One site. So, if Alabama is like most markets, on average, there is likely only one site in the market that will not get upgraded.
With those kind of odds, I wouldn't get worked up about it. Especially since a good chunk of those that will not get upgrades are likely to be replaced with a new site nearby.
Robert