Unregistered but just got big bill..some questions.

So I just got 2 bills through my door with the same bill date. 1 for all of 2015 and 1 for jan-march 2016.  Some questions I need answers to before I think of paying up:
1.  thought there were no bills being sent out during the suspension period??
2.  there was a boil water notice in my area from January to October last year..thought I read there was a rebate if that happened??
3: both bills say theyre unmetered, but there was a meter fitted outside my place in july 2015, so whats the story there?
As I said I need these answered pretty well before I think of paying up because lets face it...the timing of getting a 324 euro bill through the door in January could be better.....