Further capability enhancement of the Sentinel R Mk1 platform could be achieved through an incremental upgrade programme, adding additional sensors relevant to the maritime domain, such as Automatic Identification System, and Signals Intelligence."
In other words, if we spend a lot of money, we could give the Sentinel the same capability as has been carried in the Sentry for many years.
(I am not saying that the Sentry is an MPA either, God forbid - it just has the capability that the Sentinel is advertising and much more besides).