Well the question is: are they gonna prorate salary or earnings.
Note that due to the nature of signing bonus, if they play half season, Tavares still makes about 10.5 out of 11 mils. Now, if they prorate his actual earnings over a full season, that would mean a cap hit of about 21 mils, wouldn't it? 10.5 /41 games means 21/82 games.
This issue was not a problem at the last CBA, but now there are way too many players which have the salary mainly as signing bonus, and there are rumors many GMs/owners don't like this. I expect to be some discussions regarding this in the next CBA negotiations, and it will be interesting to see if they decide to simply prorate the salary or earnings.
There are few players in the league with similar structured salaries, and if this becomes an issue it will probably hit a third of the teams. But if the Leafs end up signing AM/Marner/Nylander to similar contracts, they would have the most money tied in such salaries.