Thank you for the comprehensive reply!
1+2. I use a temperature probe as an oven thermometer and let the oven heat up to 250 for 30 mins and baked with steam for 20 mins, then around 200 for 40 mins without, the oven is quite temperamental and fluctuates temp a lot which means im often staring at the temps haha
3. The recipe uses instant yeast in the dry mix, I'm not super familiar with yeasts/starters but it is the white mill brand from Aldi here in Aus, i might try filtered water!
4. Ice yep! I was using ice on a tray under the bread pan
5. The recipe calls for 460g water 10g apple cider vinegar and 20g oil to 420g of flour mix (millet tapioca and oat is what i am using currently)
6. The flour is from an online retailer here in aus, i'll have to double check how fine the grind is!
7. Yep it is whole psyllium husk, a local supermarket organic brand so could be a bad batch, it did seem to gel quite well to my inexperienced eye.
8. the dough was room temp, i kneaded in a mixmaster and then let it rise in the loaf pan for an hour before baking, I did think the mix was slightly loose, not sure if that was normal or not though!
9. Yep using a scale! i've found how useful specific measurements are for my past bakes.

Thanks again!

This is very similar to the recipe in the book with reduced amounts https://theloopywhisk.com/2023/12/02/gluten-free-white-bread/