It seems like M116 SHOULD work, but does not. Here's a quick test...maybe I'm doing it wrong. That last G28 is called immediately, even though bed (and extruder) are way above the target temperature.
Thanks for any assistance.G21
G28
G1 Z10
M190 S35
M104 S100
G4 P5000
M104 S0
M190 S30
M116
G28