League football operations manager Mark Evans issued a statement on Monday, saying Gieschen's six-week holiday had been planned last year.
"Jeff Gieschen is on long-service leave that was booked in December last year to take into account an important family milestone," Evans said.
Gieschen is due back at work in mid-July, and Evans said suggestions he would not return were "fanciful".
Gieschen came under fire early in the season following a confusing explanation of the pushing rule on Fox Footy's 'On the Couch' program.
Of the TV appearance, AFL CEO Andrew Demetriou said: "It wasn't one of his finest interviews."
Rowan Sawers is leading the umpiring department in Gieschen's absence.
