Or do you mean the 19 of those 39 that earned a first division, and would have advanced? Divided equally over 5 areas, that's 4 or 5 bands per area. However, it's not equal, as you'll see below.
Look at the entry numbers.
Area West (ATSSB Area) has 14 bands in it from regions 1 and 6. That one might work.
Area Central has 11. Pushing it - getting small - but you could justify it. Regions 8 and 16 contribute here.
Area South has 5 bands. Region 11 sent 4, region 12 sent one.
Area East has exactly two bands. One each from Regions 21 and 4.
And, my personal favorite - Area North has seven - all from Region 7, so their region MC is the same as Area.
Is it worth holding a separate contest for that few?
I'm not getting into which bands/regions actually earned first divisions, I was solely looking at entries for this.
IMO, it's absolutely not feasible to host separate area contests with numbers this small. You can propose they add it to the 2A/4A/6A contest if you like, but that's an advancing contest, so they may not want to add bands. Those area contests are already super long unless they're split to three sites (many are two - one 2/4A, one 6A) and even then the numbers are much lower.