I see there is something that might be doing this in the Filter Setting button.
But what I would like is a way to set a value per filter and have the focuser move to that location.
or
Have the focuser module focus after a filter change. Problem with this choice is the auto focus doesn't work for me (it creates donuts from tight stars then fails).

I''d prefer a hard setting that I find with my Bahtinov mask. Example:
LP 49909
Red 49879
Green 49864
blue 49849
HA 49909

When the filter changes, move the focus to these values.

You can set filter offset in Ekos / CCD. Look for a filter settings (funnel icon) right to filter wheel selection drop-down - the first row of controls on CCD tab.

Yup, that's the "Filter Setting button" thing I was talking about.
But how that works is a little confusing. Off Set? Is that +/- the main number shown in the first item called:"Flat Focus Position"?
How to change that first position (because it's not correct based on my earlier adjustments).

Let's assume you always focus with LP filter. Offsets for your setup would be:
LP: 0
Red: -30
Green: -45
Blue: -60
HA: 49909 0

It's getting that initial number. You would think that window would pop the current position the focuser is currently on. It seems to just be different than what my final focus was.

Example, I just focused and it is 49884, but the "Funnel Icon" shows it as 49879.

So I guess I would put an offset even for the first selection. Kinda odd. That number should be the same as I just focused to.

Question, I run through all my filters and focus each one. I see in the "Funnel" icon those positions per filter. Excellent.

Now how do I get the focuser to move to that position when the filter is changed?
Clicking the Autofocus just starts the whole focus over again. I'd like it just to move to the position found in the above exercise.

EDIT:
Ok, I got it to work, but I have to do the math... not tough mind you. just typing out the numbers. Seems a nice thing to automate. Maybe it is and I haven't found it.
Maybe every hour or so, the focus module can run through the filters and focus them, redoing those numbers. Shouldn't take more than 5-10 minutes. Especially when you are close to focus in the first place.

Might be a cool thing to have a button to calc the offsets (saves writing down the Flat Focus Positions then finding the Offsets) . I know it's lazy, but this could be worked into process that does this when all filters are focused.