have you a mobile broadband package on your phone, or are you just using the access which the phone browser uses?
having said all that, from my experience up here in th enorth-east near newcastle, the traffic updates are not all that useful. Any alerts when using the navigation usually appear to late to do anytning sensible,
If it reroutes, it tells you that it has done so, but not what the issue is. it usually warns of congestion when ther is none, and vice versa.
Also there are some major roadworks on my commute, which have had a 3 mile diversion, as access round the roundabout has been restricted. The information from wayfinder has been crap, and does not reroute via the diversion. I don't have any comparable experience of the competitors traffice such as tomtom, although I prefer the app over the garmin i3 i used before I got wayfinder.
The other thing that really bugs me is the fact that the camera warnings (which seem to be frequently and accurately updated) warn of cameras near the route on neighbouring roads, whereas it should only warn about the cams on the bloody road you are actually on! the classic example being the one one a road crossing the motorway about 1//4 mile away, but there is no junction with the motorway - utter madness!