Uber and Lyft drivers are planning a two-hour strike in several major cities around the world on Wednesday, an effort that is meant to coincide with Uber’s forthcoming IPO. Labor groups organizing the strike are protesting the companies’ payment and labor practices, and they hope to stymie the ride-hail apps during the crucial morning rush hour on the day before Uber is expected to debut on the public markets.

Ride-hail drivers in New York City, Philadelphia, Boston, and Los Angeles are scheduled to go on strike from 7AM to 9AM on Wednesday, May 8th, according to the New York Taxi Workers Alliance. Drivers in several cities in the UK, including London, Birmingham, Nottingham, and Glasgow, are also participating in the work stoppage, Uber is expected to go public at an eye-popping $90 billion valuation on May 9th.

Uber knows it has a driver problem. In its filing with the US Securities and Exchange Commission declaring its intention to go public last month, Uber said that driver dissatisfaction was likely to increase as the company sought to reduce the amount of money it spends on driver incentives. “Further, we are investing in our autonomous vehicle strategy, which may add to Driver dissatisfaction over time, as it may reduce the need for Drivers,” the company notes.

Uber and Lyft drivers in New York City got an earnings bump recently when the city council approved a bill requiring ride-hail companies to pay drivers at least $17.22 an hour. The new wage law relies on a so-called “utilization rate,” which accounts for the share of time a driver spends with passengers in their vehicles compared to the time spent idle and waiting for a fare.

An Uber spokesperson didn’t respond to a request for comment, while a spokesperson for Lyft said that driver wages have gone up over the last two years. Neither company would say whether they planned to use cash incentives to entice drivers to break the strike.