TDCC M2/8?

My Google searches got me as far as learning that the "M" stands for
Motor Carrier, that the "2" would be the version, and the "8", the
release, but that isn't much help. I seem to recall that at some
point the TDCC standards were basically implementation guides for X12
transaction sets, but I don't recall when that occurred. Would M 2/8
correspond to an X12 version and release, and if so, which one?

Thanks,

Mike Rawlins