Why did grocers union set deadline?

What's a union to do? Your members really don't want another strike and yet they also figure that six months of deadly contract talks with Vons, Ralphs and Albertsons could easily turn into nine or 12 months as far as the supermarket chains are concerned (labor negotiations have been known to drag out for years). So Socal locals representing the United Food and Commercial Workers went on the media offensive by setting a June 21 deadline for the chains to come up with a final offer, or else. Or else what? Well, that part is unclear. The union said it would hold meetings for the rank-and-file on June 24 and then ask members to either vote on the contract or vote to authorize a strike. But if the union shows little enthusiasm to walk off their jobs - back-to-back strikes are extremely unusual - most of the leverage would still rest with the chains. In announcing the June 21 date, leaders from all the locals took pains to stress that the deadline is not confrontational and that there's still plenty of time to do a deal. Indeed, there has been considerable progress on the key issue of health coverage, but they haven't gotten as far on raises. LAT SD Union-Tribune