Something I noticed on the wiki is that for Burnout I and burnout III it says the duration is 15min. However for Burnout II it says that it scales. "9.7 minutes @L29 to 15 minutes @L47"
http://wiki.project1999.com/Burnout_II
Not sure if burnout II is just different or if they all should be 15 min. I'm currently level 42 so I'm setting a timer for 13 min based on the scaling listed on the wiki.