Yes. If you order multiple audio transfers and select the MP3 option for all transfers, all MP3s will be put (in different folders) onto one CD (or DVD, up to the maximum capacity of a DVD).
"I just wanted to let you know how pleased I am with the latest LP-to-CD transfer you've done for me. As usual, the sound improvement is amazing, and every detail is perfect. There are some older LP records that have never been made available as CDs, and I think I've sent you five or six over the past few years, and I've been extremely happy ..."