We played the whole 3 hours from 1 - 4.
It was kinda stressful at times and I'm slightly disappionted I couldn't get more kills but me and Callum got a reasonable amount.
The clan level will go up to 23.
Just realised I was incredibly stupid, killstreaks count towards your total kills and I used specialist instead. Guessing I would have had at least another 50 kills if not more