I know! I was gutted! The story was incredible and they just left us hanging.
Amazon has started production on a Stargate series as of now though! There's literally no other information that I can find... for all I know they may continue Universe.
Oops! That's the one I meant, actually. The cliffhanger will haunt me for the rest of my life lol.
Also, on a more positive note, there's more Stargate in production via Amazon. Hopefully they knock it out of the park!