[Glencook-fans] Order for Star Fishers?

Hi. Just wondering if anyone can tell me where "Passage at Arms" fits in the Star Fisher trilogy. I know that it's a stand alone and that it was written after the trilogy, but I found it listed in one place as book "0" of the trilogy. Should it be read before the other three, after the other three, or does it not matter? Thanks for any help you can give, Richard