If you're going off the Lavers Liverpool Tide tables, then Llandudno is 1/2 hour previous and Abersoch is 3 hours.
The tide doesn't matter that much at Porth Ysgo - most problems are barely affected.
Angel Bay, Pigeon Cave Boulders and Porth Oer are a different matter though - and don't even bother going unless it is fresh and windy.