The above photos are a mix from the www I put together in a few minutes. I have a large collection of MTO "Mitchells" with all possible (some of them wrong) insignia used during different periods. Most of them don't follow the standard information we get from books and written sources neither do they comply with orders issued by the authorities. Yellow, red, blue borders, overpainted, added wrongly, than deleted etc. is how it was in the reality. For sure it was not the case that in the night of 14-15 August 1943 all men available have been engaged in overpainting the red borders of the insignia with blue.
340-th BG. is probably one of the best examples for these discrepancies.
I'll try to upload some of the most eye catching samples and put them here in the next days.