Looking for the source of this Pancharatra passage

[V Subrahmanian]

In the Bhamati for the Brahma sutra bhashya 1.4.21, Sri Vachaspati Misra cites a passage, a full shloka, as that of the PancharatrikaaH:

एतदुक्तं भवति - भविष्यन्तमभेदमुपादाय भेदकालेऽप्यभेद उक्तः । यथाहुः पाञ्चरात्रिकाः - “आमुक्तेर्भेद एव स्याज्जीवस्य च परस्य च । मुक्तस्य तु न भेदोऽस्ति भेदहेतोरभावतः” ॥ इति ।

The meaning of the verse is: The difference between the jivatma and Paramatma lasts only till mukti. In mukti, the jiva is non-different from Paramatma since the factor that caused the difference earlier is no longer there. 

Is such a bheda-abheda stance taken by the Pancharatra? From what appears on the face, both the Dvaita and Vishishtadvaita schools do not accept the above position. They are known to be followers of the Pancharatra. 

Any leads to the source text of this Pancharatra verse is welcome. 

Thanks and regards

subrahmanian.v