GAS ampzilla grandson

I have emailed GAS 2 times with no response and need info on a Grandson of Ampmzilla.
Does anyone know if you can run a bridged mono channel while running a pair (L/R)of 8 ohm speakers. I know its stable to 2 ohms but can you use the (2) negative R/L as a bridge for a sub?? Thanks........ Joe S
Of course the Grandson can be bridged.
I owned a Grandson it does not have the external means to easily be switched to mono. Though I believe it is possible to bridge internally but GasAudio could best answer. I too am having trouble getting their website up