Since installing version 5.5.2136 on my Acer AC100 server running Server 2012 R2 Essentials I have issues with it going to sleep at strange times, not waking up on schedule and generally just not working properly. I removed all the calendar entries for shutting the server down and it still goes to sleep at was once the scheduled sleep time. I wake it up manually and it just goes back to sleep a short time later (within the next 30 minutes of the originally scheduled time). The system log says the sleep is being initiated by loservice so it appears that even though the calendar has been modified the timers do not stop happening.
Most days it will not wake up on its own either, I have to physically power it up even if the wake time on the calendar had passed. On days that it did wake the server it was exactly 1 hour past the scheduled wake up time. I did not have these issues with 5.4.2055 version so I am reverting to it for now.