Basic question about Fresco pixel and live brushes

Thanks so much Michael. This is my first time painting in Fresco so progress was slowed last week by my learning curve.

For this picture book project, I definitely prefer the painterly look. Being a print project, I set up the 8 files with 350 dpi. After drawing their compositions in vector layers I'll ultimately hide, I began painting in pixels. Approx halfway finished painting the first spread, that question occurred to me of enlarging some created objects, snd I realized I needed to understand this in general. I was hoping that when using the move tool on a pixel layer to scale it up, Fresco would automatically adjust the pixels to the 350 dpi setting, so that I'd have that flexibility with all pixel layers, just like making such adjustments in real oil painting. Your answer indicates that it doesn't, but that a small enlargement works. Can you clarify how much roughly? Is 10% ok? Or can I simply tell if a scaled up object will print pixelated simply by the screen presence or absence of pixel artifacts? 

Also, what if I now increase the dpi on the files from 350 to 600, including this one already painted at 360 dpi. Could I then scale up the pixel layers already created approx 10%, without pixelization of the brushwork rendered before the dpi change? 

Of course 600 dpi will make the files large but I shouldn't have app performance problems if they are stored in the Cloud. Perhaps I could also lower each finished file's resolution back to 350 or 300 in Ps before placing in the InD book layout, although I'm not sure if that's an issue once exported as PDFs for print.

Anyway, thanks again Michael for your input!