The censure debate is scheduled to take place March 24-25, with the opposition allocated a total of 28 hours to grill the prime minister, says chief opposition whip Pakornwut Udompipatskul.
Speaking after a meeting with representatives from the government and the cabinet, Mr Pakornwut, a list-MP from the People's Party (PP), said the two-day debate is expected to conclude shortly before midnight on March 25, with a vote of no-confidence on March 26.
He said opposition parties were allocated 28 hours to question the prime minister, while the government and cabinet were given seven hours to address the questions. Two hours were set aside for the House Speaker and his deputies who oversee the proceedings.
Mr Pakornwut said all sides agreed to keep objections at a minimum to ensure a smooth debate and adhere to the schedule. However, the opposition plans to use all 28 hours and if the debate extends past midnight on March 25, the vote could be scheduled for March 27.
The meeting to allocate the time came after the opposition agreed to omit Thaksin Shinawatra's name from the censure motion and replace it with "a family member".
While Ms Paetongtarn is the sole target of the upcoming debate, her father, widely seen as the de facto leader of the ruling Pheu Thai Party, is expected to be frequently mentioned over allegations of undue influence over the party.
Opposition leader and PP leader Natthaphong Ruengpanyawut said the debate will focus on Pheu Thai Party deals in which family benefits come before the country's interest.
He said the public can expect to hear a variety of phrases, not just "a family member" during the debate and the revised motion means the opposition can discuss other individuals linked to the prime minister's family if necessary.
"We believe the government doesn't place national interests first. It prioritises the Shinawatra family's interests," he said.
Mr Natthaphong said several issues to be brought up during the debate are in-depth information that is never disclosed to the press.
While the information may not be enough to warrant the removal of the prime minister, it could provide grounds for lawsuits that might subsequently lead to her removal, he said.
He insisted the outcome of the no-confidence vote will determine if the prime minister can hold the coalition together.
"The debate will highlight cracks within the ruling coalition and prove that an internal rift is its main problem. It remains to be seen whether the prime minister will personally answer the questions or ask other ministers to do it on her behalf. This will help us see the picture clearly," he said.
Observers say the debate will test coalition unity because it singles out Ms Paetongtarn and as symbol of unity, every coalition MP is expected to fully back her.
PP deputy leader Sirikanya Tansakul said the handling of economic problems will be a key focus of the debate but declined to provide details.
"And we aren't targeting the former prime minister. We'll be focusing on Ms Paetongtarn...as she isn't the real prime minister," she said.