manual reboot firmware update

Hi all. I just updated my AC-88U formware to AC88U_386.2_4 and it seemed to complete ok. I got the usual prompt to "restart the router manuall". When i then did, it wont come back on ! The router shows a flashing power light (first light in the row), then briefly lights up the Internet and...

Hi. Noticed a strange thing. My RT-N66 started asking for manual power off and on after each firware update. I remember that it flashed perfectly without any manual manipulations last year. But now it asks for manual reboot after every firmware update. Any ideas? Or it is ok for latest builds...