After a few people calling with the problem of their S4's showing flashing 8's in the display; we found that they are holding the Yellow+Red buttons down too long. When you want to set or change something that requires the double button press, you should depress the yellow button and hold down while pressing the red button and immediately release both for the setting to take.

You can also jam the programming by holding the buttons down TOO long. We had a situation yesterday that proved vexing. The S4 would not stop displaying Batt 8.6 after the all 888888 problem. Removing power, "factory reset", and other ideas failed. Disassebling the timer and removing the eprom solved the issue. Nerve racking you can be sure but the fellow on the other end of the phone had a steady hand and that solved the problem with minutes to go before the first run.