Join Date: Oct 2006
Location: London, UK
Programs: BA Gold, VS Silver, SQ Silver, IHG Plat Amb, Hilton Gold, Marriott Plat, Accor Silver, Radisson Prem
Posts: 16,873
On-board upgrades are not advertised, and can only be bought onboard if seats are free by asking the CSD (Cabin Services Director). For uprades to CW or F, extra meals must also be available.
They are actually poor value for money, so think carefully whether you really need an extra 7" legroom and slightly wider seat/slightly more recline. These are practically the only benefits of WTP over WT.