Is there a successor version to ACKS "first edition"?

I recently found my pdf of ACKS, dated 2003 and labeled “First Edition”. Is the current version on DTRPG materially different? Put another way how do I identify the latest edition?

It’s not materially different, no. There hasn’t been a “second edition.” I think we just got over-optimistic about how soon we’d release another edition!

Thanks for the continuity in a great project.