It’s unlikely that Lancasters were produced by Austin in 1941 as the first production Lancaster made its first flight in October 1941.
This from Wiki .
Avro received an initial contract for 1,070 Lancasters.
[13] The majority of Lancasters manufactured during the war years were constructed by Avro at its factory at
Chadderton near
Oldham,
Lancashire and were test-flown from
Woodford Aerodrome in
Cheshire. As it was quickly recognised that Avro's capacity was exceeded by the wartime demand for the type, it was decided to form the
Lancaster Aircraft Group, which comprised a number of companies that undertook the type's manufacture, either performing primary assembly themselves or producing various subsections and components for the other participating manufacturers.
[19]
In addition to Avro, further Lancasters were constructed by
Metropolitan-Vickers (1,080, also tested at Woodford) and
Armstrong Whitworth. They were also produced at the
Austin Motor Company works in
Longbridge,
Birmingham, later in the Second World War and post-war by
Vickers-Armstrongs at
Chester as well as at the Vickers Armstrong factory, Castle Bromwich, Birmingham.
Belfast-based aircraft firm
Short Brothers had also received an order for 200 Lancaster B.Is, but this was cancelled before any aircraft had been completed.
[20][21] Only 300 of the
Lancaster B.II, which was outfitted with
Bristol Hercules engines, were constructed; this had been produced as a stopgap modification as a result of a shortage of Merlin engines due to fighter production having higher priority for the engines at that time.