I am not sure exactly what frequency combinations will be used in the "multi-frequency" mode.
BUT, I am nearly certain that yes, at least SOME of the frequencies will be able to be run "simultaneously." I think it's been made pretty clear that you can run the Equinox in a "single frequency" mode, or in a "multi-frequency" mode; there is also some video out there which IMPLIES that there will be a "different" multi-frequency mode available for the different detecting modes. In other words, if you are in "park" mode, you can choose either 5, 10, or 15 kHz SINGLE frequency, or you can choose MULTI-frequency, in that mode. Then, in beach mode, if you choose multi-frequency, it seems to be implied that this will be a little bit "different" of a "multi-frequency" mode than that used in "park" mode.
Obviously, the details are sketchy at this point, but I definitely do believe, from what I can glean from all sources, that the machine can be run in one of several SINGLE frequencies, OR, in a multi-frequency mode that will include at least a couple of different frequencies running simultaneously.
Steve