Having it set to 16 hours would still cause every NB to happen twice every day alternating between three exact times, causing the schedule to look like this (I will use the 24 hour time format for easier reading)
monday 0 16
tuesday 8 24
wednesday 0 16 (wednesday's 0 is the same time as tuesday's 24)
thursday 8 24
and so on
You can see that the three different times (0, 8 and 16) have NB consistently every other day, allowing people to easily adjust to that
The game already gives you tools to tell when the next BG is going to happen (the timer on the BG window) but tbh I don't think it's even that complicated to keep track of because you know for sure that each of the different hypothetic NB times (0, 8 and 16) will have one guaranteed BG every other day. I bet it would be much easier for people to remember that than for the VGN devs to code an uneven BG schedule (I don't know if they can even do it but I have the suspect that the SB engine doesn't simply allow for uneven BG schedules)
Oh and having slower NB schedule would also encourage people to play it more since its unique drops would increase in value over time while also not being so slow that it throws off people's daily SB routines (but then again that's IMO, more people should post their take on that and I just noticed there's another thread up there talking this same subject with a lot more people in it)
Yea it would be cool for the peeps working on VSB to give info about that so everyone can think for what works best