Take it for what it's worth, but Bovada has Game 1 happening Saturday at 3 PM. With that said, they also have the Sixers-Raptors series starting 11 AM that day, so it could be a placeholder but many also assume that maybe it means Sixers-Raptors begins Saturday afternoon, and our series begins Saturday night.
Also, the Bruins-Jackets series schedule has been tentatively released though it will be confirmed once the Caps-Hurricanes series ends tonight (Game 7). That's important to monitor because Game 5 of that series would likely be sometime next Saturday, 5/4 (Game 5) at TD Garden. And I'd assume Celtics will play Game 4 next weekend as well at home (so likely Sunday). So if I had to guess, we'll start Sunday, play Game 2 on Tuesday, and then either have 2 days off between Games 2 and 3 OR 3 and 4, then play Game 4 Sunday at home.
I have to assume they'll release the schedule later tonight/tomorrow morning, or at least release when Game 1 will begin for a lot of the series (even if the rest of it is not completely figured out). There will be games played Saturday so I think they HAVE to release who plays that day at least 2 days in advance.