The outcome of an inquiry into the botched calculations that left Dargavel Village in need of a second primary school is expected in June.
A further update has been given to elected members on the external review which is being led by former local government chief executive David Bowles.
The probe was ordered after it emerged Dargavel Primary School, which opened in January last year, was too small to meet the needs of its growing catchment area.
Analysis from Edge Analytics recently predicted the number of pupils could peak at 1,131 by 2033 – but also said space may be needed for as many as 1,500 if demand was to continue long-term.
Initial calculations, dating back to around 2017, projected the roll of the school in Arrochar Drive, Bishopton, would not exceed 430.
Alan Russell, chief executive of Renfrewshire Council, told councillors in December that the review had begun and it was estimated it would report by the end of April.
However, that timeline has since been adjusted and while Mr Bowles is at the final stage of his investigations, it is now intended that a report be presented at full council on June 22 – instead of May 4.
The local authority previously confirmed its plan to publish the final report in full, subject to "legally confidential information", with elected members given the opportunity to consider it ahead of the meeting.
"Work is ongoing on the external independent review being completed by David Bowles and it will then be reported to a future council meeting," a spokesperson said earlier this month.
"As indicated at the outset, it’s important Mr Bowles is given sufficient time to complete his investigations and fully report and the intention is to publish the final report in full, subject to any legally confidential information.
"All elected members will have the usual opportunity to consider the report in advance of the council meeting and scrutinise its content at the meeting."
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