The Union Jack Club does allow officers in but you pay a little more than the ORs
Ring, ring....
"UJC, Can I help you?"
"Can I book onto th UJC for the night please?"
"Certainly Sir. Are you an Officer or Other Rank"
"Whats the difference?"
"£25 per night"
"I'm an Other rank thanks"
"excellent, your confirmed as booked in"