This is what I get for trying to do this before I need to get some sleep. I s-off'd my M8 just a few minutes ago, and installed TWRP. Now I can't get out of twrp. If I reboot it reboots right into twrp. So I tried flashing CWM in fastboot mode, and it still boots into TWRP. However if I go into twrp and select reboot into recovery, it reboots into CWM. So if I go into CWM and select reboot system, it goes to TWRP. Somehow I have two recoveries on here. I'm really tired and would love to get some sleep.