Ryanair uses all the runway.

[The Ancient Geek]

For the non-pilots reading this, Clearway and stopway are two different things.
A stopway is an area beyond the designated runway available as extra stopping distance. It may be surfaced with an energy absorbant material. This is clearly inside the airport boundary with no obstructions. Bristol does not have a stopway.
A clearway is a fan shaped area beyond the runway with no obstructions above the minimal angle of climb. Runway 27 at Bristol has no obstructions beyond the ILS antennas because the ground falls away so if you can clear the ILS you are away free. Other airfields will often have buildings, trees etc obstructing the approach and climb out paths to consider.