Just over a month ago, my flight with BA from Boston (BOS) to London (LHR) was cancelled about half a day prior to departure, after I already checked in online. Long story short, I finally made it to London over 24 hours later than originally planned. While speaking with the customer service to rebook on another flight, I was told that the reason for cancellation was "shortage of aircraft".
A few days later I submitted a compensation claim to BA for the late arrival (£520) plus actual expenses during the extra stay in Boston. Considering this was for a family of 5, the total compensation amount is a bit under £3,000.
When I submitted the claim, I received a response that "due to a very high number of requests, it may take some time to process my claim", etc, etc.
My question is: how long do I wait before I start escalating? It's been 5 weeks since I submitted the claim. And, the follow-up question: how do I escalate?