I am not a plasterer and I only have my one pebble-tec pool to show as experience.
I only know what I was told with my pebble-tec, plasterers said no brushing necessary for smoothness just to sweep the loose pebbles to the drain to be filtered out. I think they said to sweep it 3-4 times, but it has been 2 years and I really don't remember exactly how many times they said sorry. They also said to wait for several days before using the auto cleaner, so most of the loose pebbles are swept/filtered out on the chance that a pebble may get stuck in the gears of auto cleaner.
I have heard others say plaster or pebble-tec of course you brush, several times a day for a week or two.
I have also heard others say to wait 2 weeks before you put in the auto cleaner because the plaster is still soft and you may leave wheel marks in it. The may be right for normal plaster but for my pebble-tec that seems overly cautious, I watched the last plasterer walk out of my pool on the brand new pebble-tec! There were no foot prints and he was a big guy, so I really can't imagine the auto cleaner leaving wheel marks.
Give your plaster company or contractor a call to see what they recommend, as they will be the ones giving warranty.
I'm not so sure you will have the high ph to worry about as I think some prefer a high ph cure is better.
Maybe bumping this to the top will inspire other's that are more knowledgable on the subject to advise.