If you aren't using any status benefits, then it would be best to just retro-credit everything and fly without any FFP numbers.

Note that when you credit something to A3 for 0 miles, it is still counted as credited and you can't easily "uncredit" it to claim again with AC.

You can't be sure that T on LX4671 will be T on AC160, but there isn't any way of knowing in advance unless you've credited it before.

This thread perhaps could be moved to the A3 forum as there are some Canadian posters there who may be able to provide more advice on what to do if you have *G status.