Once again, SEPTA officials have pushed back the estimated launch date of SEPTA Key, the transportation authority’s new farecard system that will someday replace tokens and tickets on Philadelphia’s buses, trolleys, subways and commuter trains.

In an exclusive interview, SEPTA’s chagrined general manager, Jeff Knueppel, said that a launch decision will be made April 15th, following a meeting with ACS Transport Solutions Group, the Xerox subsidiary overseeing implementation of the new payment technology (NPT). If the payment system gets the green light then, an official SEPTA Key launch would happen about six weeks later, in early June.

And if ACS and SEPTA don’t think the new system is ready after the April 15th meeting? Well, you’ve waited this long, right?

SEPTA officials had previously hoped to begin the NPT system’s launch in April. SEPTA Key’s arrival, now well over two years behind schedule, has been delayed by the project’s unexpected complexity and software bugs.

SEPTA Key will initially replace monthly and weekly transit passes only, so don’t throw out your tokens just yet (or at all: Eventually, you’ll be able to trade in tokens for credit on your SEPTA Key cards). Rich Burnfield, SEPTA’s Chief Financial Officer, said that SEPTA Key’s availability may also be limited at launch, meaning not every monthly or weekly transit pass holder will be able to upgrade to SEPTA Key immediately.

SEPTA Key will also rollout first on SEPTA’s buses, trolleys, and subways. Regional Rail and Norristown High Speed Line would implement SEPTA Key many months later.

Burnfield justified the limited debut by pointing—once again—to Chicago’s troubled rollout of its own NPT system in 2013, saying a smaller launch would help SEPTA identify and fix problems before offering the Key to everyone.

SEPTA is the only transit system servicing a major American city still using tokens.