Last season the NHL used a traveling taxi squad to try and alleviate COVID issues, but the league opted not to put this in place this year, but appears to be changing their stance on this.
NHL/NHLPA working on COVID roster protection, including: Optional use of taxi-squad through All-Star; emergency call-ups as long as player is making no more than $1M; and freedom to add a goalie if a club has less than 2 healthy due to the virus. There are some rules on who is eligible for a taxi squad, including clearing of waivers and time spent on an NHL roster.