Something to declare: Where to go, how to save, what to avoid

Destination of the week: The club-class cabin

British Airways has quietly introduced a cut-price upgrade system for those flying in the cheap seats from Heathrow. The airline has long offered on-the-spot upgrades from Gatwick on European flights; currently £60, £80 or £100, depending on the length of the flight. Now, at the airline's main base, a one-way upgrade to Club Europe costs £100 for shorter flights such as Paris or Amsterdam, while the furthest destinations, such as Athens and Istanbul, are priced at £150.

You get a higher baggage allowance and access to the executive lounge at Heathrow, as well as more space and better catering on board. Long-haul passengers can also opt for upgrades to World Traveller Plus, for between £180 and £250. Crucially, though, you cannot ask for one of these upgrades, and they are not on sale at the airport; the airline offers them to economy passengers, by email, for flights that have space available.

In a separate move, BA's inflight magazine is about to go beyond the seat pocket: from Thursday, it is online at bahighlife.com.

Warning of the week: Blue alert

The tsetse fly spreads serious diseases in Africa, and is definitely an insect to avoid. In a story on this page last week about travellers' insect myths, we stated that tsetses don't like the colour blue, and repeated an assertion that wearing blue denim can repel the tsetse fly. This turns out to be plain wrong.

Val Berry was the first reader to get in touch: "In Botswana, there are huge billboard-like structures covered in a sticky substance and acting like giant flypapers – they are painted blue and dark brown because these colours attract flies.

"In any event," Ms Berry continues, "on safari one should always wear green and coffee/beige to merge in with the bush. Blue, white and red are discouraged by park rangers as the animals spot those colours easily."

Bargain of the week: Latin America on the cheap

The Spanish airline Air Comet may be unfamiliar to many travellers, but it is currently undercutting the market on flights from Gatwick via Madrid to Havana, Quito, Guayaquil or Bogotá (above) for a flat return fare of £480, if you book before Tuesday (7 October). The deal applies to journeys completed by 5 December.

Test bookings suggest that availability is rather patchy, with the best availability in November. Note that the website (www.aircomet.com) does not appear to allow bookings any further than Madrid, so you will need to book by phone on 0871 222 0330.