Not quite. A large Indian outsourcer won a large part of work to maintain the CA7 schedule. Anyone has worked at a bank knows that the batch schedule is somewhat mystical and was put together by guys who had been at the bank for 20 yrs - replacing them with bright, but fresh out of uni, offshore outsourcers was a large part of the cause of the 2012 outage during an upgrade.
This outage hit the NatWest batches. The NatWest batches are far bigger than the RBS, Ulster(s) and IoM/Courts and are the first to run over and the hardest to rerun before the next batch window. So it looks like to me that a file was blocked causing the backlog (and no one noticed quick enough).