Hi NancyJ,

I did a test on my end and it looks like the field you're looking for is:

This field contains all the returns set for e-filing, so you'd need to add on "US-STI". So if it currently is "US,CA" like in my test, you would set it to "US,CA,US-STI". I have not tried to write to this field myself, but don't see why it wouldn't work.

Let me know if this helps!

Best,
Steffan