↑The New Essential Chronology states that the Ruusan Reformation occurred in 1000 BBY, which is the zero point of the calendar based on the Ruusan Reformation, so the difference between the calendar based on the Battle of Yavin and the Ruusan Reformation's year-notation system is 1,000 years. This date is derived using simple math based upon other confirmed dates.
↑In Chapter 18 of Children of the Jedi, Leia states that Irek "had to have been at least four years old" when Leia first encountered Roganda before the Battle of Yavin. This was referenced in The Emperor's Pawns, which states that Irek was eight years old at the Battle of Endor in 4 ABY. However, this reference was ignored by later sources, such as The Essential Guide to Characters and the Jedi Academy Training Manual which sets Irek's age at 14 in Children of the Jedi, which would place his birthdate as 2 BBY. For the purposes of this article, the original 4 BBY date is used.