Question for YYZ Arrivals

[gr8gazu]

This may already have been addressed but a recent Cat III dicussion triggered a memory thus a question.

Last year during a couple of fog days in YYZ, approach clearances were being given only to Cat II aircraft. During our 1 1/2 hour hold, the RVR fluctuated a few times to the point that it was well above the Cat I approach ban, and for extended periods, but approach clearances were only being given to Cat II.

This was around 22:00 local so volume was not that much an issue.

Any comments that might help for planning during future low-vis days?