This is the third time in the past 8 months something like this has happened. The first time - as new users of QBO - we panicked thinking we had lost our data (even though it's cloud based). Then after a few hours it was all back, along with many duplicate transactions because we couldn't find the POs we were creating and kept trying to create them over and over.

It happened again a few months ago. Same exact issue that lasted a few hours (right in the middle of the day conveniently). I can only suggest hanging tight and wait for things to come back. It's just a matter of checking until you see things return to normal... since there is no communication from QBO on what has happened or when it will be restored.

Needles to say (and I'm sure I know I'm preaching to the choir) but this should not be "a thing" with a global cloud accounting system used by huge numbers of individuals and companies all over the world. 

Shame on you QuickBooks!!