Stillman was put on waivers Saturday for the purpose of assignment to AHL Rochester.
Stillman (upper body) is expected to return to the lineup Thursday versus Dallas, Bill Hoppe of the Olean Times Herald reports.
Stillman (upper body) will remain out of the lineup Tuesday versus the Islanders, Mike Harrington of The Buffalo News reports.
Stillman (upper body) won't play Monday versus Edmonton.
Stillman left Saturday's game against Tampa Bay due to an upper-body injury and won't return.
Stillman has been activated to the roster on Thursday.
Stillman has been placed on the non-roster list while working through the immigration process, Bill Hoppe of the Olean Times Herald reports.
Buffalo acquired Stillman from Vancouver on Monday in exchange for forward Josh Bloom.
Stillman registered an assist during Monday's overtime loss to the Devils.
Stillman has been in the press box during the Canucks past six games.