Galaxy Note 10.1 (2014) SM-P601 has not received 5.1.1

[Android Central Question]

Hi. My Galaxy Note 10.1 (2014) SM-P601 has not received the 5.1.1 upgrade. It is still on 4.4.2. I've tried to manually have it search for updates but tells me that the latest updates have already been installed. Is there any reason for this, or a way to have it update itself?