I've read a few times that we are in the middle of phasing out single hull tankers for all double hull not sure what the status is of this. But in the interim you would have a tanker glut.

But those would have been scheduled replacements, and then there is NEW capacity.

If they accelerate the replacement/retire of older fleet with NEW capacity, still leaves deliveries of tankers on the books that are not needed...so will still lead to a crunch in shipbuilding in the near future.