I had my iphone 4 in airplane mode, i have a password on it, and it got stolen. If my phone were to die(battery depleted), and the theif charges it, will airplane mode still be active?

My phone was recently stolen while in airplane mode. My phone was locked. If the phone dies and the person who took it charges the phone, will airplane mode still be on? Also, can my service provider do anything to find it if it is in airplane mode? Can my service provider locate it if airplane mode does turn off if it does so after being charged? I do not have icloud setup on it and its an older version.