I cannot remember two weeks closed..never happened!
It certainly used to happen when I was going when it was LMP at Lancaster Gate, they had a couple of weeks off in the summer, I recall Moss mentioning they were going somewhere exotic abroad. I went to LAPC while they were shut, no comparison to LMP but ok for the cost for me.
They used to state they were closed on their site and I see they state the same on this site, closed till 3rd September for a summer break.