Just some information that was useful to me:
I emailed the McMaster PA program and I can confirm that supplementary application will be emailed out mid-February. On Feb 21, the online submission (through Mosaic) of the supplementary application as well as the fee (by check or money order) is due.
On the topic of transcripts, I emailed both McMaster and OUAC. If you a submitting your transcript to McMaster through OUAC, make sure you have indicated in the transcript request for "immediate" submission, rather than end of Fall, etc. OUAC is backlogged on transcript requests so it may take a week from the time of the transcript request for them to send it out. McMaster also needs another 5 business days to process the transcripts. Good news is that McMaster will see the time stamp when you put in the transcript request, so as long as this is before Feb 1 you will meet the deadline even though your Mosaic profile still says the transcript request is "initiated" rather than "completed" on Feb 1.