Greetings. The filter position values are already stored in the Autorun Log files which you can access from the ASIAir app or in the logs folder on your USB stick. Example entry:
2020/11/07 23:49:37: Find Focus Point: detect and calculate star HFD 2.2 , EAF position 3524
I don't think it would be wise to put those values into the filename. It's already long enough if all the available options are enabled. I.e.
73 characters. I think that is enough already 🙂
I still would prefer a dedicated flat mode as i once requested here: https://bbs.astronomy-imaging-camera.com/d/14164-asiair-feature-request-add-dedicated-flats-mode Looking at you to respond, ZWO.