Few vids and topics on the interwebs say as long as you have sync 3.0 you can upgrade , but when I use my vin on the ford site it says my software is up to date 

If you want to update a car with Sync3 3.0 to 3.4 you’ll need to leave the support of Ford and taker a look at Cyan Labs. Input your VIN and they will compile an update for you with the latest version of Sync and Maps.

Cheers Andy, I presume this would invalidate any ford warranty re sync 

If you use Cyanlabs to update your sync 3.0 to sync 3.4 then Ford will no longer offer you any software or map updates for Sync. You will need to get those updates from Cyanlabs going forward.

Being cautious about this there would be no guarantee that Cyanlabs would/could continue to offer updates in the future and probably nothing to prevent them from charging for future updates if they decided to do so. Having said that, several people on this forum have gone the Cyanlabs route and seem perfectly satisfied with it.

Ford continue to offer firmware and map updates for Sync 3.0 at this time. 

I decided not to move from Sync 3.0 to Sync 3.4 as the benefits seem very small to me.

 

I went from 3.0 to 3.4 with Cyanlabs as I thought the benefits were significant. It does have a much nicer look, backgrounds can be changed, I get radio logos and I get Google Maps and Waze instructions echoed to the screen in front of me when using Android Auto. It was a very easy process and map updates appear much quicker than using the Ford system. Besides, as your car is 2017 and nearly 5 years old I am not sure what warranty there would be on your system.