This release has an updated macOS 10.12.2 MAS URL after the MAS release was updated on December 15th 2016.
To help minimise the number of pull's required to keep MAS assets updated, they're now maintained in a seperate file which precache.py will remotely query. This should make it much easier for ensuring your cache keeps updated.
This release also changes what Software Updates are cached - from now on, only macOS related combo updates will be cached.