One stays in the jinn state in accordance with one's capacity, level of being, and the will of divinity.
Regarding one's return to the original point of departure, yes. We return in the same position we left.
As for shapeshifting and having one's clothes still on, I do not know. It would seem that clothes would vanish as one takes on animal form, as depicted in the art of the jaguar knights and other Aztec and Mayan initiates who achieved jinn metamorphosis.
For thirty years I sought God. But when I looked carefully I found that in reality God was the seeker and I the sought. -Bayazid al-Bastami