if a weaving draft calls for 12 epi and 12 ppi (alpaca), but your alpaca is 16, what does this do to the draft? Can I use it? Thank you.

Your project will be slightly bigger - multiply your # of ends by 16 and you’ll see how wide in the reed it will be.

What are you weaving?

I'm confused is your alpaca yarn recommended to be woven at 16epi but you want to use it in a draft that suggests a yarn sett best at 12 epi?
Did you want to keep the same width but a different yarn?
Or Did you just want to weave at 16 epi?