Republican Gov. John Kasich signed Ohio’s Senate Bill 5 last night. The bill limits collective bargaining powers for the state’s 350,000 government employees, and requires public workers to pay at least 15 percent of their health-care premiums.

But it’s not clear when the law will be implemented. While it is currently scheduled to take effect in 90 days, that could change if union advocates succeed in getting enough signatures (around 231,000, which is 6 percent of the votes cast in the last gubernatorial election) to halt the bill’s implementation until a statewide referendum vote on the measure can be held in November.