It is pretty simple. If you are managing to play, you are getting 7 free days and you are happy.

If you are not - say you can only play after work, and you try over and over again to queue to the game but aways get the 2002 error midway, so it is not a matter of waiting in line. You actually cannot play at all - that is another story.

You payed to play for 30 days. In nowhere it is said you can only use these days out of peak time. But during 7 of these 30 days, SE did not provide the service you paid for. So you paid for 30 days of service and got 23. SE doesn't have to give your money back, because it is smart and put that in the EULA. But it doesn't want you to stop paying for it every month. So it will gice you 7 extra days. You paid for 30 days and will get 30 days with a 7 days iatus. The first group got 7 free days though