Hi @Jack-the-Lad
I watched the live Newcastle v Arsenal match on Sunday and didn't notice a delay of the kick off time when watching on NOW.
Though I am not a BT or BT TV customer, where if you was experiencing a 10 minutes delay then that would be totally unacceptable in my opinion.
There would be a time lag latency delay unfortunately when streaming over the internet compared to watching over the air or Satellite, but this is usually under 2 minutes from my experience, where it is the same if you compared watching a live event on BBC iPlayer against Freeview where the BBC iPlayer would lag behind.