That's how I always read the "10 days of darkness." A major reset that allows the 60% to happen behind the scenes, and the 40% to be set up to explain it on day 11. Wells Fargo recently had a deposit snafu, any deposits made via ATM didn't exist. It took them 10 days to work everything out. Test? Perhaps.
BB&T bank also had similar issues recently, delayed proper balances for just over a week.
How many problems have banks had recently that locked people out of their money? How many times have transaction systems failed, leaving debit cards useless for a few days?
It's getting more frequent, and no reason has been announced.