[panative]

Pennsylvania German/Deitsch comes from Pfälzisch and as spoken by plain people mostly branched off in the 18th and 19th centuries but influence from other German speakers and especially English didn’t stop in time then.

It is much closer to standard German than any dialect of Dutch. Amish read the Luther Bible (mostly 1912 edition these days) in German and sing the Ausbund in German but don’t otherwise use “Hochdeutsch” in everyday life, and they exclusively use English for reading and writing outside of church.

It’s also very important not to confuse the Amish and their language from other plain Mennonites and Anabaptists who speak Plautdietsch which is a completely different low German language and not intelligible with Pennsylvania German or standard German at all. Many of them came from Germanic peoples who were settled in Poland, Ukraine, Russia etc.