Yep, way before Ptolemy. I think it's 900 BC. Ptolemy was 125 BC, and Nathaniel was AD 2005(ish, depending on book).
I liked the return of Faquarl; he and Bartimaeus make an awesome duo, even though they don't like each other. Yeah, Asmira was a bit annoying - I'm happy she stopped being so "ILOVEMYQUEEN!" in the end.