Another potential road block has emerged in the LIRR's effort to meet the federal deadline for installing Positive Train Control.

The federally required safety technology was ordered by Congress back in 2008 after a train crash in California. It prevents collisions on the rails by automatically slowing or stopping trains that violate stop signs.

In a letter last week, MTA chairman Patrick Foye told Amtrak's chairman that he recently learned Amtrak won't have the agreed upon software in place until next spring.

Foye adds, "The revised Amtrak schedule now shows this B2B software update to be delivered in May 2021. I find it shocking that Amtrak has not yet contracted with either Burns, Siemens or another contractor to perform this critical B2B interoperability work."

Amtrak responded Thursday, saying "Contrary to the information in your letter, we have a task order in place..." It continues on to say that although particular software won't be ready before the deadline, "We are confident that, working together, we can have an acceptable mitigation solution that will allow us to safely operate trains through Harold Interlocking and achieve FRA compliance by the deadline."

The MTA missed its first deadline in 2015, and was granted an extension to December 2018. That deadline was also missed, and was extended to this coming December.

Both MTA and Amtrak officials say they do believe PTC will be installed in time for the December deadline. But Amtrak's proposed alternative for the B2B software still needs approval from the Federal Railroad Administration.

Both teams are scheduled to meet again next week.