Pitkin isn't big enough to house all of the cars that run on the and Rock Pk .207th would still be used for storeage if it does become the
main shop for the line.
I don't see the R143's leaving the line,ENY has 208 R143 cars.that isn't enough for service and you would need over 300 R179 cars to cover service.the line won't see any new subway cars until the R68/A cars retire.
Just because there is one trackway from the going to 207th St yard doesn't mean a thing,that yard is big enough to maintain the lines subway cars alone.