No formal announcement has been made about former Atlas tooling which used TMCC. The MTH tooling Atlas has purchased the rights to use will apparently, and unsurprisingly, will be offered only with DCS/PS3.0. Probably too difficult and expensive to redesign for another system, and, more importantly, the factory has no experience installing TMCC/Legacy.
Makes sense but it will be interesting to see how this affects Atlas sales, since most surveys suggest the installed base of TMCC is substantially larger than DCS. This isn't surprising since TMCC was around for six years prior to DCS's availability (approximately 1996 to 2002). PS2 appeared earlier (2000), but not the TIU/remote to control PS2 in command mode.