It was the first experience for us to do bisque wood firing on August 1st. It took 18 hours for wood, also plus gas preheating. A week after the firing (8/7) , we unloaded kiln.
Potters used to use wood kilns for bisque firing long time ago in Japan and usually it's updraft kiln. As far as I know, there are several Mingei style pottery villages which still do bisque wood firing in Japan to keep their style as analogue. Our kiln (second chamber) is downdraft, and we were not sure if it's OK, but it seems like everything went well.
A photo below is at the Kanjiro Kawai Museum in Kyoto, Japan. (Kanjiro Kawai was one of the leader of Mingei Movement) It's no longer used because it's not allowed to use wood kiln in Kyoto city any more.
In addition, Japanese potters fire bisque at 700 to 800 degrees in Celsius (approx. 1300 to 1500F) and it's much higher here as you know. I don't know why there are such a difference between US and Japan. Maybe because clay bodies are finer here? but there are lots of fine clays in Japan. This time we stopped firing around 800C and we hope it works. We'll see.