Weird writing mistake

Every now and again I make weird mistakes, but I often don't find them until days or weeks after I wrote them. Here's one from Sergeant Dunn novel #18. And I had to read it twice to realize the problem.

This was to combat the constant Allied bombing, both day and night that took place day and night.

See it? Yeah, there you go.

Highlight and use my friend:

Remembering D-Day - 6 June 1944

Remembering those who stormed the beaches in Normandy on this day, 79 years ago. In less than a year, the war was over in Europe.