I originally posted this in
another thread:
Article 22 of the Montreal Convention doesn't actually differentiate between delayed and lost baggage and, under the convention, you can purchase replacement items for up to 1,131 SDR (GBP1,047.15):
In the carriage of baggage, the liability of the carrier in the case of destruction, loss, damage or delay is limited to 1,000 Special Drawing Rights for each passenger unless the passenger has made, at the time when the checked baggage was handed over to the carrier, a special declaration of interest in delivery at destination and has paid a supplementary sum if the case so requires.
(The 1,000 SDR limit was increased to 1,131 in 2009. See U.S. Department of Transportation, Inflation Adjustments to Liability Limits Governed by the Montreal Convention Effective December 30, 2009, 74 F.R. 59017-18 (Nov. 16, 2009)
I'd try to be reasonable with it, but you can force BA to adhere to the Montreal Convention.