Thank you, Alex, for information about "Poltava affair". Unfortunately I don't have it, and probaby it's unavailable in any library in Cracow...
That's true, Trzebinia oil refinery bombing was so accurate, that the target need no "replay". Here
http://www.geo.uw.edu.pl/WIEK_NAFTY/36katastr.htm is a photo of destoyed refinery (bottom left).
I found a story about raid to Trzebinia in Home Army partisan's memoirs, this incredible scene really raised their morale!
August 7.
In the noon we watched an interesting occurrence, which had strengthen our spirit very much. A flight of English planes flew exactly over our heads. There were maybe 200 of them. All of them white, wonderfully sparkling in the sunlight! They headed northeast, unhurriedly and firmly, as in their own country! No German planes pursued them, but after a short while we heard shots from machine guns.
Note that every four-engined plane were called “English” – they knew about Polish bombing squadrons in UK and mostly named B-17s or B-24s as “Lancaster” (or even “four-engined Wellington”!). “White” color surely was the aluminium.
Best regards,
Piotr