WATCH: Overtime strike by STM maintenance workers could mean bus, metro delays next week

Starting Monday next week, about 2,400 STM maintenance workers will refuse to do overtime — and that could be just the beginning of a full-blown labor dispute between the transit agency and its workers.

On Wednesday, several hundred STM workers, including maintenance workers, bus drivers and metro operators, demonstrated in front of the STM's headquarters outside Place Bonaventure to protest lagging contract talks.

Union stickers have also started appearing on STM property, including buses and metro cars.

Maintenance workers say they're short-staffed, and want more mechanics to work nights when the buses are off the roads. Union rep Dominique Daigneault, meantime, accuses the STM of cutting back on their services and expertise — even going so far as to accuse them of trying to privatize what they do.

The overtime strike by maintenance workers could lead to delays along certain bus lines, although Daigneault insists the workers will be there if there are any major breakdowns.

Meanwhile, bus drivers and metro operators are set to take a strike vote on Thursday, something which could lead to a full-blown transit strike somewhere down the road. If that happens, essential services would have to be provided — which in the past has usually meant morning and afternoon rush-hour service, and late-evening service.

Maintenance staff demonstrating outside @stminfo offices, set to strike next week from any overtime, Which is a problem because since most of them work daytime when most of the bus fleet is on the roads, not enough will be serviced when they need to be and so delays are expected. pic.twitter.com/RPGCm1kudO

— Andrew Brennan (@ACJBrennan) May 2, 2018