Yes, the Z270 motherboard supports a quad-channel memory configuration.
Yes, the Z270 motherboard supports a quad-channel memory configuration.
Hey fellow Z270 enthusiasts, I was searching for a Z270 motherboard supporting 7700k with quad channel memory. It seems even the premium ASRock Z270 SuperCarrier only offers dual channel. Is this the only option available or did I overlook something? Appreciate the advice! 
The service supports only two channels. Dual channel options are available on HEDT platforms, but quad channel isn't currently offered.
Yes, you're correct. Doubling the capacity to 32GB keeps the bandwidth unchanged while increasing the storage space.