The charter amendment bill is expected to go through a post-scrutiny debate in parliament next month before being put to a vote in September, according to Paiboon Nititawan, chairman of the committee scrutinising the bill.
Mr Paiboon said on Sunday the committee will meet on July 27 and 30 to iron out differences and amendment issues.
After the panel has wrapped up its work, it will present the revised version of the bill for a second-reading debate later next month.
The committee will likely finish its scrutiny on Aug 7, said Mr Paiboon, also a list MP of the ruling Palang Pracharath Party (PPRP).
After that, parliament will deliberate the bill at its second reading towards the end of next month. Fifteen days later, there will be a vote in the third and final reading. After the legislation clears parliament, it will be forwarded for royal endorsement.
But before the bill is presented to HM the King, lawmakers reserve their right to ask the Constitutional Court to rule on any legal queries with the amendments, highlighted by a proposed switch from a single-ballot election system to a two-ballot method.
However, Mr Paiboon said he was confident the changes to the election system will pass parliament given overwhelming support from the PPRP, the main opposition Pheu Thai Party and the coalition Democrat Party.
There are also 210 senators who voted to adopt the bill in principle. Support of at least one-third of the Senate, or 83 senators, is required for the bill to be enacted.
Meanwhile, the opposition is aiming to deploy a censure debate next month as a democratic means of expelling Gen Prayut Chan-o-cha from the premiership over the government's failure to contain the Covid-19 pandemic, said chief opposition whip Sutin Klungsang.
Mr Sutin told the Bangkok Post the no-confidence debate, to be held for the second time this year, is the opposition's most intense measure for keeping tabs on the government.
He believed the debate will be held next month before parliament goes into recess in September.
If enough no-confidence votes were cast against Gen Prayut, he would be removed from office, prompting his replacement through the parliamentary process.
Other candidates on the list are Bhumjaithai Party leader Anutin Charnvirakul, former prime minister Abhisit Vejjajiva nominated by the Democrats, and Khunying Sudarat Keyurapan, Chadchart Sittipunt and Chaikasem Nitisiri, all of whom were proposed by the Pheu Thai Party.
"But if none of these candidates win acceptance from the people, the next prime minister will need to be another non-MP," Mr Sutin said.