Work Over pay 250 extra  

...kind of like coming in a few minutes early so you don't catch a late flight and get to go home on time.

The pilot you relieve early is there for 12-14hrs based on a defined shift time. Anything that happens during that is that pilot's responsibility. When you start earlier, you effectively end up with less time available for the end of your own shift. If "everyone does this" that is no different than having a scheduled shift start time. You log the start of your duty time correctly for the earlier relief, right? So you end up with less than 2hrs of 135 duty available to you at the next shift change (assuming 12hr shifts)... and you turn down a flight for that and we will want to know why you were coming in early. You just log shift times even though you started working early? When you get that late flight that hits that 14hr mark and someone notices you were at work early and performing work duties and we see you weren't logging duty time correctly.... you will have a problem.