Single KG30 aircraft attacks Bridlington 11 Jul 40

my Grandad witnessed the plane coming over Melboune, he could see the pilot it was that low, also my grandma on my dads side was at work in Derby and watched it fly over also very low, both still alive today and remember it like yesterday. I know it was the HQ of the Royal engineers that was bombed. Would this be a significant target and the training depot was at kings newton. a similar bomb pattern as to the Bridlington bombs was in Melboune. I live opposite the site of the first couple of bombs which didn't make a lot of damage. Assuming these were c50s. It was always said they were after rolls Royce as it had Melbourne pool and church painted on. I personally think the Royal engineers HQ would be a good first target and also ammo depot's maybe in tutbry, burton and Bridlington.