आगमे वैष्णवे विश्वासटिप्पन्यः

Hari Rao (1976) dicusses how the Kōyiloḷuku, the Śrīraṅgam temple chronicle, describes in great detail the substitution, by Rāmānuja, of a Vaikhānasa-based system of temple-worship for one based on the Pāñcarātra Saṃhitās. However, this did not signal the end of this competitive rivalry, since from 1223-1225 CE, Śrīraṅgam was occupied by the Oḍḍas, the army of the Eastern Gaṅga King Anaṅgabhīma III, who reinstated Vaikhānasa ritual practices throughout the short period of their occupation (Spencer 1978: 18). - Leach

Kanchi’s vaikuntha perumal temple was built in the eighth century. (though currently it follows vaikhanasa). Such changes have happened due to disturbances - Trivikrama temple of kanchi was originally vaikhanasa but now following pancaratra. - ravilochana