There are in the neighborhood of 150k members, 15% (16,500 signatures) are needed by September 23 to force a vote of no confidence. If the necessary signatures are finally obtained and validated by the club, the 'true' machinery of the motion, which involves a vote in which a minimum of 10% of the member census participates requires 2/3 of votes against the president for it to succeed in the removal of Bartomeu from office.
Allegedly, despite the COVID situation, the collection of votes is moving along well but important to note a President has never been ultimately removed by this process. This censure was attempted very recently against Bartomeu and only achieved 12,500 votes (They look to be sure to surpass this). Rosell & his cohorts did similar against Laporta in 2008 before Pep's arrival and it led to a vote of no confidence (They only got 60%)
This was the breakdown last summer of current club census