I've got a subdivision that had an alley along the outside perimeter. A later plat subdivided the adjoining property. Some time later the alley was abandoned. Does the entire alley go to the lots that adjoined it in the original subdivision, or does half go to those lots, and the other half go to the adjoining lots in the newer subdivision? This is a Tennessee survey.
In every State I work in, the Alley property would stay with the original dedicator. Havent surveyed in Tennessee since '81 so ymmv...
Here it would go to the subdivision of its origin. I always think of the outside boundary of a subdivision as being similar to a section line. If it came from only one side of that line then it stays on that side of the line.
If the lot owners received fee title to the beds of adjoining dedicated roads and alleys, they did so only to the extent that the fee to the lot and the fee to the dedicated area came from the same grantor.
I've found with alley's, at least in my part of the world, it will depend on how it was deeded to who. Though abandoned, it doesn't cease to exist and there has to be a title transfer from the town/county that it was reserved for. I've never run into one though, that deeded to somebody that didn't purchase within the original subdivision.