View source for Talk:Merits/@comment-31.54.101.205-20170303002105/@comment-76.235.25.214-20170324205456

They expire at the reset of Power Play (currently 7 AM GMT every Thursday); but only that amount required to reach the next rating tier.  To illustrate:

You're trying to reach rating 3 (750 merits) by the end of this week's Power Play rotation.  You fall short of your goal and only manage to earn 500 merits.  For the following week's Power Play session you will be considered rating 2 as that level requires 100 merits.

Those 100 merits will be deducted from your pool of 500, leaving you with 400 merits.  The good news is those 400 merits carry over to the next Power Play rotation, so you effectively start off that week having already "earned" 400 merits.

You then go on to earn another 400 merits next week, giving you a total of 800.  With the start of the third Power Play rotation (third in the context of this discussion), you will be rating 3 as you reached the 750 merit threshold.  Those 750 merits will be deducted from your pool of 800, leaving you with 50 merits going into that third week rotation.

If you want to maintain your rating 3 level, you'll have to earn at least another 700 merits in that third week to add to your 50 merit carry over.  Fail to do so and you'll be demoted to the next lower rank (or even lower if you fail to earn enough merits to meet even ''that ''rating level threshold).