Flying out there on the 9th so will ask when I go to the lounge. I tried to find the email I got about it recently where it said status member plus upto 5 guests during the summer but i've deleted it. I was somewhat confused in getting it as i'm 'new & Blue' but i'm hitting Silver in under 6 months as a leisure traveller so maybe they were trying to encourage me to continue current habit's regarding travel ( or more likely it was genericaly sent to all)
Will report back once I've asked( if nobodies nailed it by then). They're a pretty friendly bunch so I imagine subject to capacity they'd be fairly open to it anyway if you were GGL.
Just an additional bit of info that at LGW you can't pass through security more than 7 hours before your flight ( somebody recently complained about that fact so it's apparently a thing)