It seems to be, according to media sources, that it's all going to be covered. All the phones HMD has made will be getting Android 9.
A public Android 8.0 Oreo beta has arrived for the Nokia 8 ahead of the phone's official OS update. The 3, 5 and 6 will follow soon.
As the brand licensee for Nokia smartphones serves Asia, where the number 4 tends to be a homophone for "death," perhaps we're better off with a Nokia 2.