This summary is not the rule. The rule text controls.
When someone is charged with a crime, the charging papers don't have to list the exact date and time the crime happened. Prosecutors just need to say the crime happened sometime before the charges were filed, as long as it's still within the legal time limit for bringing that charge to court.
There's one exception to this rule. If the exact timing of the crime is actually part of what makes the act illegal, then the timing does need to be specified. For example, if a law only makes something a crime when it happens during certain hours or on a certain date, that detail matters and must be included.
This rule exists because in most cases, the exact minute or hour a crime occurred isn't what makes someone guilty. What matters is that the crime happened and that charges were filed on time. This gives prosecutors some flexibility, since victims and witnesses don't always remember exact times, especially if they're recalling events from weeks or months earlier.