Between 7 and 10 days seems an awfully short time when it’s really 4. They did take their sweet time sending the I-797 we were expecting. Apparently they received it on the 6th, the notice date is the 10th and the official notice arrived today.
Ah well, I’m not complaining. At least things are moving :). Our guesstimated NOA2 date is between October 16 and November 4, about 5 months from now. Untill then, it’s fingers crossed and waiting patiently.