welcome to the board, SYOT, feel free to start a little thread to introduck yourself. Wait, strike that. Intro
duce yourself.
You are correct, but iirc, the music was originally published in that tuning, in order to use more open chords for beginner and intermediate players. A more "standard" key, at least for rock or folk players.
http://www.jdarks.com/files/shipoffools.html has it in Bb, hth