I was also playing around that that property to see if it had an influence on the page positions
But, I might be wary about how those are linked!
Specifying whether a page is on the left or right side of a layout influences things like float: inside|outside; and margin:inside|outside; which change the actual layout of elements on those pages.
The pdf-page-layout is only (if I understand correctly) an indication to the PDF display software for how that document should be displayed, and these may be ignored, irrelevant, or changed by the user.
Since it might be "bad" to have actual content layout shifting around because of a pdf display preference, I would suggest that, if there's a direct or inferred link between these two aspects, that the pdf-display follow under the influence of the page-position: left|right; property, rather than the other way around!