Best overlap: 8:00 AM to 4:00 PM in Toronto is 10:00 AM to 6:00 PM in Brasília.
Both teams are at their desks between 8:00 AM to 4:00 PM in Toronto and 10:00 AM to 6:00 PM in Brasília. You won't be short on options — 8 hours of overlap leaves space for recurring syncs and ad-hoc calls alike. A quick caveat — Toronto's clocks move for daylight saving and Brasília's don't, so the times here are right for only part of the year.
24/7 support sounds great until a P1 ticket falls into the gap between Manila signing off and Dublin signing on. Here is how to design a follow-the-sun support model that actually catches tickets at the boundary. -