I also had this problem with posts not publishing while scheduled. Then I noticed that in WordPress: settings I had my time settings on UTC+1 at that moment it was 12:05 (daylight savings time in Amsterdam) but my WordPress told me 11:05. I changed the setting to Amsterdam instead of UTC+1 and noticed the time was now correct. I did a test with a new scheduled post set to 1 minute in the future and it then published perfectly. I am not sure if the problem is completely solved now but just wanted to share this, maybe it can be of any help to you too.
