This only works if you continually write them and send them in. I meant it was 2 weeks from the previous time credited. When I said they credit them about every 2 weeks, I didn't mean it was 2 weeks from the time you mail them in. I'd say a more realistic time would be more than 6 weeks. Three weeks is actually a short time from when you send them in. Mostly that I wasted 100 postcards/postage and more importantly a couple days of my time.
I've been waiting far longer than 3 weeks so I'm not sure what to think.