Very interesting update:
If you go on AC's website and search up YUL-YYZ on March 20, select AC425/427 on an A320, and look at the seat map, you'll see a configuration that you may have seen before but I have not.
12J 134Y. ( ? I may have counted incorrectly with the Y)
Could this be the Glowing Hearted A320 cabin? It has been speculated that 238 is being refurbished at YHM. Has anyone seen this config? (If it helps, there are two lone Y seats on the right hand side in row 34- seats 34E and 34F.
EDIT: found it on AC137 March 15. What is this????