Ooops, just read your updated post and see you need info about T1. That terminal only has an AC Maple Leaf Lounge, nothing else right now.
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My original post...

Yes, as noted, the KLM lounge which used to be called REMBRANDT but has been moved and reopened under another name. It is a PRIOTIY PASS lounge, but last month announced that anyone could use it for the payment of about C$25 a visit. It is located at the end of the international pier of T3. Drinks and light snacks are free, but one must purchase internet time if she wants to use the lounge terminals. It is a pleasant space and I've used it when flying WestJet. I believe it still opens around noon and stays open until about 10p or 11p. It does get crowded from 5p to 7p when the bulk of AF and KL flights depart.