I can see that those tracks or clubs buying a new decoder would be affected, but what's to keep the tracks and clubs that have existing decoders from using them and selling only the MRT transponders in the future?

It seems to me that MRT could be the big winner in all of this, since nobody would have to upgrade anything, and the MRT transponders are less expensive. It sounds like AMB are shooting themselves in the foot.

There are no features on the new AMB transponders or decoder that I consider to be useful.

It might be best to not buy any of the new AMB transponders, or buy or "upgrade" to the new AMB decoders, until things settle down a bit.