They just announced it it 2 national televisions, so I doubt it is a joke!
And knowing Vlado character I am not really surprised! He has yelled before to coaches who dare to replace him!
No, it's not a joke - for now he has the intention to leave after the league (I overheard accidently something today, I wasn't eavesdropping though! ) I don't know if that's the reason, but I wouldn't be surprised, as you say - it's too much in the style of his character