DWC 400watt semi sealed co2 closet

Lights just came on and to my surprise i noticed 2 plants i had determined to be females due to twin hairs were growing male flowers( im currently around a week into 12/12). Is this common?
So now im left with only 1 viable female snow white ( out of 5 germed - 3 were males and 1 died from stem rot) and my 4 clones of unknown strain.
Pics below
Yellow highlight indicates the males that were there
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