For one thing I didn't feel a dip in the energy levels all day. Not even in the evening when I missed my nap.
Because of my evening social engagement I knew I would not be able to get my nap but it was fine. Even playing sports was fine, I didn't drop from sleep deprivation in the middle of running around.
Didn't even feel sleepy in the train home, just tired.
I came home quite exhausted last night but even though I was free to go to bed at 2300, I made a superlative effort to stay up till midnight, so as not to mess up my routine completely.
Because I was expecting to be very tired and sore today, and knew that my body needed extra time to recover esp. as I don't play sports usually, I decided to do a limitless monophasic sleep. So went to bed at midnight and turned off all alarms.
Funny thing is, I still woke up at 0537 and could have gotten up but deliberately went back to sleep. I knew I have to be active all day tomorrow so I have only today to recover completely. Woke up again at 0630. Slept some more. Then finally at 0711 I realized that I would have to get up.
So, that's one more change from biphasic. Just as I can fall asleep very quickly, I cannot sleep very late in the morning, even if I have time and physical fatigue. Early rising I'd call a good side-effect.
Actually, I wasn't half as tired or sore as I was expecting to be. In fact, not sore at all, just tired arms. I think stretching before sports, and before going to bed might have helped with that.
About 1100, I did feel sleepy again, so took some more freestyle sleep. It was less than 2 hours and quite restful.