Check this out. DX-World just released this announcement from the WSJTx developers. Will it be backward compatible or will everyone have to update their program?
Paragraph 2 is most interesting:
But rather than sending concurrent streams of up to five FT8 signals, the SuperFox station will transmit a single constant envelope, using a 1.5 KHz-wide waveform, that conveys signal reports or “RR73” acknowledgments to as many as nine different Hounds simultaneously. Most importantly, there will be no signal-strength penalty for simultaneously transmitting to all those Hounds.
73's
George - WB5JJJ
HoIP - 100105