I built a Standard Legal Deck using deck builder. However, the program is listing it as "Vintage." I reentered using just the  main deck and it is properly listed as "Standard." However, as soon as I enter any/all of my sideboard cards (it doesn't matter which SB card I enter) the deck is then categorized as "Vintage." Is this a known issue?

I reentered several times and it finally took as a Standard Deck.