One posible expalantion is the Julian Calendar.
British colonies in the 17th century didn't use the current Gregorian calender but a modified version of the Julian calendar which was unique for 2 things
1. The year started on March 25th (Jesus' incarnation according to tradition).
2. It was 10 days delated from the Gregorian calendar.
So way back in the 17th, the year 1692 in british colonies ran from March 25th, 1692 to March 24th, 1693.
Which adjusted to the Gregorian Calendar would be April 4th, 1692 to April 3rd, 1693.
This is even more confusing if we take in count that Salem witch trials ran from february 1692 until may 1693.
As a conclusion, it can be said Melinda Warren didn't add the first page of the book, and the person who did it, must had been confused because of the lag caused by the differences between calendars.