Is this a young Halibut?

Is this a young Halibut?

Observation - Is this a young Halibut? - UK and Ireland. Description: Around 20cm long, found on shoreline. Not sure which species. Here is a Halibut farm nearby and the peck-marks (from a gull?) make me wonder if it was from the farm.

Around 20cm long, found on shoreline. Not sure which species. Here is a Halibut farm nearby and the peck-marks (from a gull?) make me wonder if it was from the farm.