Trash_Buffet You can have as many chapters as you want and release them when you want within the prompt timeframe, also long as you write to the total word count, and per chapter word count. It also must be a new story to webnovel.
WN release the prompt on the TGIF notification, to give writers time to plan and stockpile before the prompt officially opens.
Since power stone votes over time determines the rank places, it really pays to come out of the gate fast and furious with mass released chapters or a solid chapter that will sucker in further read interest. Then continue to pump out regular release updates to retain readership and hopefully draw in new ones.
Everyone one has their own method of meeting to the prompt. The common theme is keeping the story going at a regular pace to ensure power stone votes remain steady (as can be) and maintaining to that word count. Since you want to gain a high number of votes at the end to be in to win.