@A Squared
Besides, it looks like nobody really knows whose P-3s they are or what they're doing.
edit: I see a later posts suggest that they are US P-3s searching for MH370
Old news (yesterday) - Australia offered two of its RAAF Orion PC3s to assist in the search -
No Cookies | thetelegraph.com.au
These are probably already based at Butterworth (adjacent the Straits of Malacca) where the RAAF has had a presence since the 1950s.