New Phone - Google location not syncing/sharing to desktop

I've just got a new phone (Oneplus 3 from old Samsung S4), and I'm having issues with location in Google Maps - I'm trying to share my location with family (via G+ app), but overall I'm seeing some odd behaviour.

If I go to Google Maps on my device, my location is correct.

If I go to Google Maps on my desktop machine, my location is wrong (out of date from the time at which I swapped mobile devices)

My G+ location is also refusing to update - showing the out of date location on my desktop, and on the G+ app on my device putting a red dot for me in the correct current location but with the text of 'old location 19h ago'.

Stuff I've tried:

• Check location sharing is on (both pinpoint and city) in G+


• Check location is on in Google Maps 'Google location settings'


• Check location history is on in Google Maps


• Logging out of Google Maps (on device) and logging back in again


• Closing Google Maps (and G+) apps on my device


• Check correct device enabled on Location History (via Google Maps)


• Check location is correct in Google Maps (on device)


• Check I'm signed in on the same account with device, G+ and Maps (I only have one)


• Try Android device finder from desktop (it is correct!)


• Try 'Your Timeline' >> 'Today' in Google Maps on desktop (it is correct!)


• Turning device off and on again (multiple times)

I'm running OxygenOS (3.2.5), with Marshmallow (6.0.1)

Any ideas?

Thanks!