The longest standing rock group from the British Isles that is still performing and that still has all its original band members is U2 (1976-the present)
Dave Phoenix Farrell is the longest longest standing bassist of Linkin Park. He has also played bass for the band The Snax.
Rolling Stones
flex band
baishnikov
Cal Ripken
Salem - UK band - was created in 1980.
Tempest - UK band - was created in 1974.
Halo - UK band - ended in 2004.
Halo - UK band - was created in 1999.
Witness - UK band - was created in 1997.
Witness - UK band - ended in 2004.
Solstice - UK band - was created in 1990.