The sleep timer is different with the update. We use this every night and when first "updated" the tv woke me up at like 2am. To set it you need to select the sleep timer, click right then go down to 30 minutes then hit enter. It will tell you how much time is left before it turns itself off. I liked the old version much better.
If you are interested do a manual system update. I just did our TCL Roku and it found 24 channels to update. This is when it said it had been updated this morning. You can find this in settings/system/update.
Roku Ultra, Roku 3, Roku 2 and Roku 1
Samsung 65 inch SUHD KS8000 using Samsung smart hub for all connections.