Is oral thrush in hiv an early symptom stage or later symptom stage?

Late, usually. Usually a sign of late infection, i.e. overt AIDS, usually several years after catching HIV. It can occur in early HIV, but usually does not. In either recent or longstanding HPV, thrush is never the only symptom. Also, most coated tongue and other white patches in the mouth are not thrush. See a doctor if you have symptoms you are concerned about.