It means you'll be seated on the side. The theatre is "U" shaped and in all probability, you'll be facing the opposite side of the theatre. Oh, you can sit on an angle to face the stage and it's not uncomfortable. Remember, this hall was designed to LISTEN to music, not to SEE a starry cast. It's not bad, though. I sat there for the legendary FOLLIES in concert, as well as for one performance of SWEENEY TODD, starring the magnificent Patti LuPone.
You might want to bring opera glasses.
"Long live God!" (GODSPELL)