This is a sub-page of Bloons Tower Defense 5 (Adobe Flash).
In the tower weapon files, some 3rd tier tower upgrade paths are ordered differently than their in-game order. These likely show a change in the upgrade ordering, or the upgrades themselves, for the certain towers during development.
Below are the orderings as listed internally to the final release. The first two upgrades on each table are for the left upgrade path, and with the last two for the right path.