A gantry spanning the motorway with blue overhead signs showing the following text.
Forward destinations: The SOUTH WEST; Bristol (West) & [Airport symbol] M5 .
Exit destinations: A38 Filton [Solid square diversion symbol].
Junction number: 16.
We’re still within junction 15, Almondsbury Interchange, but if you want to exit at junction 16 you need to leave now and fight your way across three lanes of traffic trying to join the M5 from the M4. Good luck!