Playoff tickets and dates

Sorry I'm an Australian who's coming to visit Toronto late April. The mate I'm coming to visit is a die hard maple leafs fan and i want to buy some tickets to the playoffs for while I'm there. I arrive on 24/4 and am there for 5 nights. Although NHL website says all playoffs are TBD is it safe to say the leafs will be playing in the second round? First game on the Thursday 24th and second game on the 26th? Is it safe to buy tickets on stubhub yet or should I wait for the season to finish and maybe have to pay more? Thanks.