I also use the stock Rep2 firmware. Sailfish looks a bit complicated for me. I don't know, maybe there is a setup for Rep2 in Sailfish, have not checked !!
To start the heatbed again, after the extruder has reach temperature, I have done this:
Open FFF settings, select Temperature
Select "Heated Build Platform" Set temperature for layer 1 some 10-15 deg. C more than you want when printing and check the "Wait for temperature..........." box
Set temperature for layer 2 to the temp that you want when printing.
So the Rep2 starts to heat up the bed to 50 deg. C. When the temp. is reached, it starts to heat up the extruder and at the same time cut off the bed.
The bed temp. start to decrease slowly.
When the Rep2 starts to print layer 2 it turns on the bed again and also keep the power on to the extruder
Notice that the bed is not shut down when the printing is finished.