One suggestion when you code you could make use of variables in the on and the off settings.
Why couldn't you have several variables and just go through a loop comparing them to the current time just check in on NTP in this loop and compare errr it's been so long since I've messed with ESP but I would imagine there is a way around NTP.
Oh and BTW Merry Christmas!
Where I buy my ESP8266 boards from... (Banggood)