Don't think this would ever happen. It would not feel/play right on console...
And if they did want to put Planet Coaster on consoles, they would probably just start a new game!
Invest in a custom desktop PC. Yes it can be pricey, but my system will still be moreful when PS4 Neo and Xbox Scorpio come out. And yes I have xbox 360 and xbox one.
I think this might help explain why Planet Coaster will probably not be ported over in its full and complete release. This was taken from Frontier's anual report and accounts for 2015:
PC SEGMENT - PC performance continues to improveincrementally and PC as a gamingplatform has had a resurgence. PCs offeran open platform and lead the market onprocessing performance. The low barriersto entry and performance on offer todevelopers act to stimulate a wide varietyof gaming experiences and the highestpotential visual quality, as Frontier’ssupport for 4K and higher resolutionsin Elite Dangerous illustrates.The open nature of the PC platform alsomakes it amenable to using a variety ofsophisticated third party peripherals toenhance the gameplay experience, suchas Elite Dangerous’ support for joystickcontrollers. For this reason also we areseeing the re-birth of Virtual Reality (VR) /Head Mounted Displays, leading on the PCplatform via Oculus Rift and the HTC Vive.
It continues:
Access to the console market is gated by the owners of the different platforms.