This topic is not about calendar days. It's about daytimes and night times and whether or not it was common to say that a daytime and/or a night time was to be involved with an event when no part of the daytime or no part of the night time could have occurred.
The bible isn't always very clear on day and night. You need not look any further than Genesis to determine that.
"Reason obeys itself; and ignorance submits to whatever is dictated to it" -- Thomas Paine