A New Dawn, page-72

In reality I think that the rest of the announcement speaks volumes.
Chris Burns is the core value proposition and having a small shareholding has always been an issue because he had less skin in the game. Now he has everything to work for as he IS the centre of the company.
Admiral Natter stepping up to the plate is another big one. Moving from non exec to execute director means more day to day involvement in the running of the company and can only be a good sign.
Promoting Nick with his familial connections and as someone who has "led billion dollar transformation programs for manufacturing and natural resource companies" seems like the perfect position as he makes a name for himself. He is taking half of the dual role of Suzanne Yeates who was both the CFO and secretary which surely isn't sustainable as the company scales.
In light of this, perhaps Phil wasn't providing enough value given that he isn't directly involved in the global battery market (like Chris) nor is does he have direct ties with key US governmental personnel (like Adm Natter).
He might have been more useful take over the main business of the St Bakers: Delta Electricity.
NVX would have been a great place to upskill in business development before the change of guard in the Delta chairmanship.
Trevor is likely interested in driving NVX from a less hand on position given his other commitments and therefore a non executive directorship seems like the perfect place for the major shareholder to sit.

This is all IMO so take it with a grain of salt but I think this announcement is very exciting.