BKK Photographer spotted the first truck with election campaign posters, it reminded me that the last elections for the district councils as well as the metropolitan council were already quite some time ago. In fact, they were in 2006, so the four year term ends next year. After some more searching, I finally also found an article giving the approximate dates for the elections.
Thus same as last time, the election will be split in to rounds. At first 14 district councils in the north and east of the city (see map) will see their end of term on April 29 2010, and therefore will have new election in June; whereas the term of other 36 district councils as well as the metropolitan council end on July 22, so the second round of elections is expected for September. I still have to research a lot on the local government of Bangkok, even the number of councillors I only just learned from the news article about their requested pay rise. As there are 357 Bangkok municipal councillors, the district councils cannot have equal sizes, and with the planned new district these numbers will change for sure.
As I will be in Bangkok in early June, I will at least be able to take several photos of the campaigning, but since none of the 14 district is close to the areas I normally stay I probably won't be able to do real first hand election reporting. But of course will post updates here whenever I learn new details about these forthcoming elections.