Platform_packages not being fetched on build

I’m guessing this since the 5.x upgrade this has been broken, but my library has a build (env:nrf52_express) that depends on a custom BSP. I used to be able to see the package in ~/.platformio/packages but since 5.x upgrade (currently on 5.0.1) it is not fetching my BSP and therefore failing to find the custom board I added. Any help would be great. This is on OSX Catalina.