Ottawa is 7 hours behind Kyiv
Best overlap: 3:00 PM to 6:00 PM in Kyiv is 8:00 AM to 11:00 AM in Ottawa.
For a call that suits both sides, look at 3:00 PM to 6:00 PM in Kyiv / 8:00 AM to 11:00 AM in Ottawa. You share roughly 3 hours a day. That's enough for regular meetings, but treat the window as prime time and guard it.