Guild Wars 2

Ok, so Dulfy says that guild missions reset at Saturdays (around midnight for my timezone), guild mission’s screen says we can do 25 merits a week.
So, we want to get the 80 Merits thing, we did one mission last Sunday, then scheduled another for today (Wednesday). which didn’t give any merits, i did get the chest reward and commendations from the first kill. So what gives?
Please do elaborate on how it works.
After re-examining things i’m thinking that the 25 would be from doing a tier 3 mission, but if that’s so, why say the cap is 25, and not say the cap is 1 mission a week?

There are three things you need to consider. First, you can only do one mission of each tier per week; e.g. one tier 1, one tier 2 and one tier 3. Second, you can only get a maximum of 25 merits per week. Third, you get the amount of merits indicated in the mission menu and they don’t add up. For example, if it says tier 1 gives 15 merits and tier 2 gives 20 merits and tier 3 gives 25 merits; you can do a tier 3 that will give you 25 merits. However if you do a tier 1 it will give you 15 merits and then a tier 2 it will give a total of 20 merits (5 extra). Namely the amount of merits indicated is the total you would get if you do at least that tier for the week.

Yeah, i kinda suspected that, its just that the way i read it at first, i believed we could do 2 tier ones and get 15+10 merits.
I know better now.