Dan Rosen of NHL.com was asked by a fan about PTOs...

An official start date for the 2020-21 NHL season has not yet been announced. Once it is, I expect more PTOs (professional tryouts) than official signings before training camp because so many teams are at or near the NHL salary cap ($81.5 million), making it hard to commit to another contract right away. Once camp begins, players on PTOs will be given a chance to make teams with the potential that injuries, opt-outs or other possibilities could create salary cap space. We will see players who we never thought would be on a PTO going into training camp this season on a PTO because they didn't get signed in the initial wave of free agency, and now it would be easier on teams to invite them to camp with no strings attached.

more questions for Mr. Rosen...