"There are over 70 bug fixes in this upgrade, plus a tonne of balance and feature tweaks," said Creative Assembly communications director Kieran Brigden in a post on the game's official forums. nope Amongst many fixes to crashing problems and other issues, the patch will also partially address the naval AI--though Brigden noted that the system will still remain somewhat incomplete post-patch.
"The technology behind naval invasions is actually really rather heavy and is still causing some issues," said Brigden. "The gameplay upgrade will make naval invasions possible but they will be rare. The AI now has a proper mechanism for the planning involved and can execute that mechanism when required, however increasing its frequency is a balance issue we haven't been able to get fixed in time for this upgrade."