Screen UnLock History

Hello !
Some one has secretly unlocked my phone when i was away for a few days and used some data i have saved in it to commit fraud. If i can ascertain the time my screen was unlocked i can ascertain which one of my room mates it was. I am using a Moto X second generation phone and had a numeric lock code in place.

Thank you

Based on History, when restocked?

Based on past history of Nexus devices, when will the devices be restocked after the first waved has been sold out?