Both sides had a tacit bombing truce before 10 May 1940 and imposed strict limits on bombing targets. The Germans did it because they were husbanding resources for Fall Gelb, the French because they were at the lowest ebb in their bomber rearmament and were greatly outnumbered and the British because their self-defending bomber formations had been shot out of the sky by German fighters, guided by radar.
Converting bombers for night bombing took time. The British had neglected to fit armour or self-sealing fuel tanks to their aircraft and they quickly turned into barbecues when hit. Mysteriously, French and German front line aircraft had both as a matter of course.