[Franek Grabowski]

Gents
There are a few methods to verify the story. I suppose the easiest is to ask Brian, who visits the board about his/their source. Then, there are several sources that may have yeld an answer to the question, like enemy activity reports, ultra intercepts, w/t intercepts, daily intel reports, p/w interrogation reports etc.
Finaly, borrowing aircraft within unit was pretty much a standard within RAF, USAAF or VVS. I see no reason why this could not have happenned with the Lw.