Hi @Maw -
Welcome to the forums!
There isn’t a target launch date for the Navigator rev yet, but hopefully it will be in Q2 or Q3 this year.
In the meantime, you can use the existing Navigator with the Pi 5 and the latest BlueOS 1.4 beta versions, but expect to need to disable one of the magnetometers (done under Vehicle Setup / Configuration / Compass), as the stock cooler fan is positioned very close to it and will keep it from being calibrated / used.