Change Aspect Ration in Custom Models?

Is there a way to select an aspect ratio when using a custom model?

I don’t see a way to select what aspect ratio to create an image with when using a custom model I trained. I trained the model using 16:9 images but it will only create square images. There is no selection to make any adjustments when selecting a custom model, other than a “upscale and enhance” toggle. I’ve found I have to create the image with the custom model, and then use a separate prompt to edit the image and then select the 4:3 aspect ratio I need - this uses more credits though, just to get the aspect ratio I need, so not ideal - it woudl be great if we can genertate then in the correct ratio we choose from the start.