Previously, you were able to spawn unlimited MIAs until you maxed your gun, then it would limit to 8 every 4 days.  However, once you hit maxed, you traditionally had to wait until your MIA counter reset.  Now, any MIAs shot before your gun is maxed does not count towards the MIA limit after it is maxed so that you can continue without the normal 4 day break.

On the downside, this meant clearing all previous MIAs, so everyone's counters have been reset (They still counted, we just label them differently now in our database)