A lot of dates with availability in May and June for Virgin Atlantic MAN-BOS business class for less than £ 1000. Just over 1k for flights on OneWorld.
Great to see these are still available: https://insideflyer.co.uk/2017/01/f...rect-usa-922-return-inc-summer-holiday-dates/ Makes using Avios on BA more or less pointless - especially if you live north of London anyway!