A shut down at the Windsor Assembly Plant is now into week seven.
Unifor Local 444 President Dave Cassidy posted on the union's Facebook page that production will once again be halted next week.
"On a Windsor Assembly Plant return to work date? No, we don't have any date," he wrote.
Stellantis is also unsure.
"No. I can not say for certain that production will resume on May 17. This is a global supply issue," said Head of Communications for the company, LouAnn Gosselin.
At issue is a microchip shortage that has plagued auto production around the world.
Meanwhile, Gosselin said the company hopes the shortage is resolved soon.
"Stellantis continues to work with our suppliers to mitigate the manufacturing impacts caused by the various supply chain issues facing our industry," said a statement from Stellantis.
The shutdown started the week of March 29.
