I had a mixed cabin itinery (aeroplan X/I) departing from yyz with UA econ on short leg and UA Polaris the long haul. I was denied entry to the mll at yyz transborder even though I had a same day boarding pass on Polaris. The attendant at the front kept saying it had to be business class boarding pass departing from yyz and connecting does not qualify.

I was able to access during the summer on another mixed cabin itinerary UA econ short haul connecting to BR J long haul.

The mll site doesn't specify it had to be a boarding pass departing from yyz, only that it is same day. In the summer my boarding pass from yyz showed lounge access on the pass but it didn't this time.

Should I have been able to access this time around also?