Notwithstanding section 20 of chapter 43B or any other general or special law to the contrary, in a town, 1 member of a housing authority shall be a tenant member appointed by the board of selectmen and 3 members shall be elected by the town; provided, however, that of the members originally elected at an annual town meeting, the candidate who received the highest number of votes shall serve for 5 years, the candidate who received the next highest number of votes shall serve for 4 years and the candidate who received the next highest number of votes shall serve for 2 years. Notwithstanding the preceding sentence, upon the initial organization of a housing authority, if a town so votes at an annual or special town meeting called for the purpose of organizing a housing authority, 3 members of the authority shall be appointed immediately by the board of selectmen to serve only until the qualification of their successors; provided, however, that the successors shall be elected at the next annual town meeting as provided in this paragraph.