In the current explore rate table (1A), it says, for the Republic Explore Chart, you stay at 7 acres from 18630 to 21620.

In fact, I am over 22k now and still at 7 acres per explore. I am guessing it never drops to 6. The explore table should not have an "end" amount if it never drops after that.

rep exploring doesn't drop under 7. sure that 21620 could be replaced with - but doubt it'd matter much.