By start I meant specifically material existence, the soul is eternal and has no creation nor dissolution.
There is some argument in my tradition, however, as to whether souls in material existence have always been there and can transcend into the spiritual,
or if they start in spiritual existence and choose to temporarily descend into material existence.
A third option I have considered stems from the (dogmatic) understanding that "ego-death" or merging the soul into the non-differentiated Brahman is ultimately a temporary cessation of individuality. Sort of like a reverse coma - where the soul becomes so absorbed in awareness that it seems to outshine any other aspects.
My tradition asserts that even if a soul were to remain in this divine light for billions of lives of the universe, action and individuality would eventually manifest.
And without understanding of spiritual identity and action, the soul would again return to material identity and action.
So with this re-manifesting of Self, there can be a semblance of a start to the soul, when in reality it is eternal continuance of the tatashta sakti, the marginal potency - sometimes part of the internal, sometimes part of the external.