Sinweiy, thanks for explaining further but I've read elsewhere that this is not the case so I'm a bit confused here.
what did they said?
can read this:-
http://www.kagyu.org/kagyulineage/buddh ... /cul02.php
The seventh and last quality is called the limb of perennial manifestation, which means that the Sambhogakaya cannot cease to be, but has manifested throughout the ages. There is no such thing as Sambhogakaya ceasing to exist in the way that the Nirmanakaya is withdrawn when the Buddha enters paranirvana.
Nirmanakaya and Sambhogakaya manifest in a compassionate way through four major modes. The first mode is called the "ever present manifestation of compassion," which means that compassion is inherent in the realization of the Sambhogakaya. This compassion has always been here, and because it is ever present, it is inexhaustible at the Sambhogakaya level. So even if the buddha passes into paranirvana--even if the Nirmanakaya stops manifesting for a while--the manifestation of compassion does not cease on the Sambhogakaya level.