Thanks for responding, Josh, but that is definitely not the problem for many of us. The SP4 I'm running now was swapped out at the Microsoft Store here in Austin on 2/17, so it's about as clean as possible, and definitely never had the 1/27/2016 firmware
update applied. I'd attach a screenshot, but the dreadful new OneNote won't let me save an image.
My system shows no exclamation points, yet woke successfully the first time this morning, then failed to wake a little over an hour later in the SP3 dock - a forced firmware shutdown and reboot was (again) required. I am running no better than about a 50%
chance of successfully waking from sleep after the 2/17/2016 firmware update, even if I always put the SP4 to sleep with the power button rather than closing the keyboard cover. (It's even worse otherwise.)
For those of us suffering from this problem, it is literally true that our odds are considerably better at Russian Roulette than in waking our nice, new Surface devices from sleep.
Dead solid reliable sleep/wake (and not baking the device when it's asleep in a bag) is basic blocking and tackling for a mobile device - we expect this to work as it should - and we should not have to wait months again for another "fix" that is so poorly
conceived and tested that it actually makes the problem worse for a great many users.
Kudos for the post, though - please keep us informed. We're all very frustrated and need to know that Microsoft is working on this and understands just how disruptive this flaw is to getting real work done.
Let us know if there is any info we can collect and provide that will help reach a resolution more quickly - I''m sure most of us are quite willing to do whatever we can.