Acharya Abhinavgupta a renowned Shaiva-Shakta enlightened master of Kashmiri Shaivism had numerous Gurus. While reading introductory part in one of the works of Swami Lakshman Joo, I found the following sentence -
Swamiji tells us that Bhattenduraja was not of the Trika school; he was of the Vedanta school, but he was Shaivite.
In the concluding verses also Acharya Abhinavgupta acknowledges Bhattenduraja as the master who taught him Bhagvat Geeta.
So do we find any further evidences which shows the Acharya was initiated in Vedanta school. Also, which Vedanta school he was subscribed to? As his master was Shaiva, it possibly means a Shaiva Vedanta school which is no more existing or Advait Vedanta?