Thanks @cryptoidiot.
I just saw in this announcement:
After the release on the 17th there will be just one more new network before the token generation event (TGE), at which point we will be live. The network will not be taken down after that, including for the introduction of the native token when that is ready, all updates will be made in flight, and data will be permanent.
So it does suggest this is all temporary and the plan is still a native token 