Municipal area transfer in Rayong

On Monday, the change of the boundaries of two adjoining municipalities in Rayong province was announced in the Royal Gazette. Choeng Noen (เทศบาลตำบลเชิงเนิน), located north and east of Rayong city [Gazette] and Noen Phra (เทศบาลตำบลเนินพระ), located west of Rayong city [Gazette] are connected by a narrow area running parallel north of Sukhumvit road. I wasn't able to find a map of the original municipality boundaries, but it is possible to get them by the Tambon. Both municipalities were originally TAOs covering the same-named Tambon, except those area which are covered by Rayong city, and in 1998 the boundaries of the Tambon in Mueang Rayong district were officially defined [Gazette]. Though the boundaries are only defined in written text and not as a map, by comparing the coordinates it seems that in fact the two Tambon have no adjoining area, being separated by the city of Rayong. Thus the with the announcements now, Choeng Noen gained some area west of Rayong city, with a very narrow connection of the newly gained area north of Rayong city.

The interesting question is whether this change for the municipal boundaries will also cause an adjustment of the subdistrict boundaries, to keep the two municipalities within their original Tambon.

I have tried to turn the main part of the two maps within the announcements into a single Google map, the pink boundary is the area which I believe was added to Choen Noen.
View Choeng Noen, Noen Phra in a larger map

Ko Samet district to be created - or not?

Already on December 15, the Department of Provincial Administration (DOPA) had an announcement on their website titled "จังหวัดระยองจัดตั้งอำเภอส่วนหน้าเกาะเสม็ด" - Rayong province establishs district Suan Na Ko Samet. So I thought, yet another new district to be created, this time on the small island near the coast at Rayong. It wouldn't be the only small district - the smallest district by population is Ko Kut, an island off Trat province.

However, when trying to find more details I noticed that - unlike the other island districts - Ko Samet does not even form a subdistrict, it just is one administrative village of Phe subdistrict. Starting to doubt my assumption, I looked into the name of this district, and noticed that อำเภอส่วนหน้า can also be translated as "Front part district". And there were more Google hits for this word than just those on Ko Samet, there also seem to be such districts for

• Ko Tao (เกาะเต่า), Ko Pha Ngan district, Surat Thani
• Ko Lipe (เกาหลีเป๊ะ), Mueang Satun district, Satun province

However I haven't been able to find a page which actually describes what such a "Front part district" does mean - but my guess is that it is simply means a branch district office built in the remote parts of a larger district, where the citizen can only reach the district office after a very difficult travel.