It's British Airways Short Haul Business Class service. The service definitely has its detractors – you don't get a proper business class seat. However, flights are often terrific value. You also get extras like lounge access and extra baggage.
You may be wondering, is British Airways Club World the same as business class? The answer is yes. Club World tickets offer a premium, business class flight experience compared to flying long-haul in economy.
No dress code except for staff flying on non-rev tickets. In my experience most other passengers will be dressed casually as comfort during the flight is a high priority.
If it's warm, it's OK to wear shorts. T-shirts are fine too. However, if you want to look at least halfway attractive and respectable, at least go for long pants and a button up shirt.
In other words, smart-casual is a good rule of thumb to follow when deciding what to wear in an airport lounge. This means being neat and presentable without being too formal. However, you will find that there are several airport lounges that don't care what you wear as long as you're not offending anyone.
Lounge suit is a loose term for women, but it generally means that a formal dress or outfit is required. However, it isn't quite as formal as black tie, so something like a pantsuit or floral pattern could be acceptable. For men, it's a lot simpler and means a suit worn with a tie.
“British Airways does not enforce a dress code for passengers in any travel class, a BA spokesperson told High Flyer, while Cathay Pacific confirmed “we do not have dress codes for business class flights and lounges”.
Although lounge staff is in the hospitality business, and they can enrich your experience a great deal, tips aren't expected. You can also leave lounge reviews on the Priority Pass app or website. That positive feedback can be a great way of appreciation.