If the effect on humans who live nearby and/or who use the beach did not need to be taken into account, gulls and other scavenging wildlife would gradually clear up the carcass down to the bones.
Tides at Bridlington are generally higher than we get on our wee loch. I don't know if that would mean bits of the carcass got taken back by ebbing tides.
But, since consideration for humans is necessary, what Sago suggests sounds most likely to me unless it's a small whale that can be lifted and taken to deep water for disposal. Gulls are useful scavengers on landfill sites too.