What will become of Swings on 12/6 with the 23/5?

I'm swinging stocks and 12/6 has me a little freaked out because of the move to 23/5.

I'm looking for reassurances that it won't matter if trades can happen anytime throughout the day. Or if massive moves happen once I'm asleep. Or if there are no more pre- and post-market announcements made and all of them are literally in real time while algorithms are ready to strike.

What will happen? How will 23 hours per day trading impact swing trading on stocks?