The High and low tides are due to the Earth rotating "under" the moon wich attracts a bulge of water.
So there are 2 high a day when the moon is directly overhead (more or less)
If you think of the tide being "in" as when the sea level is above the average and "out" when it's below the average then the there should never be any difference between the amount of time it's in and the amount of time it's out.
However there's a full moon on Friday (I think) and that means you have spring tides. These are nothing to do with the season but occur at full and new moons when the moon and sun are aligned. During Spring tides you get exceptionally high high tides and very low low tides.
So if your definition of the tide being in is different, say being above the causeway at Lindisfarne, you might find that the tide is "in" for longer