Developer Bovis - which is rebuilding 150 Bradford schools - has admitted it might blow its deadline of September 2002, and could lose money as a result.
The company has been awarded a £91 million contract to do refurbishment, new building and revamping at schools across the district, as part of the shift from three-tier to two-tier schools.
The agreement states all work must be finished by September 2002, but bosses at the firm say one site - Ilkley Grammar School - is "at risk" of failing to meet the deadline.
At Ilkley Grammar, one of the district's flagship schools, students are currently being taught on a split site.
Under the proposed revamp, they would all be housed on the main site at Cowpasture Road thanks to the addition of a new three-storey block.
The work is set to cost around £6.5 million - the dearest in the district.
But the proposals have proved unpopular with local residents, the parish council and Ilkley Civic Society. In total, 28 objections have been registered to the scheme.
The school's governing body is now desperately hoping the controversial scheme is discussed and approved at the August planning meeting of Bradford Council.
If a planning decision is delayed until September, it will be impossible to complete building work before September 2002 - meaning disruption for pupils will continue into another academic year.
Councillor Martyn Smith (Con, Ilkley) who is a governor, said the school had been at odds with Bovis, the contractor, but the impasse had been resolved after the intervention of Bradford Council chief executive Ian Stewart.
The school wanted a more expensive revamp than Bovis was prepared to agree. Compromise has been reached, although school leaders still feel the new classrooms are too small.
Now the obstacles revolve around the planning process.
"It might be touch and go as to whether it gets planning permission in time," Coun Smith said. "If it doesn't, the school will suffer. We are already losing teaching time, because children are being ferried about in minibuses. I understand there will be financial penalties for the contractor."
Phil Wakefield, of Bovis, said: "Everything is on target with the exception of Ilkley Grammar School, which is at risk. That is revolving around the issue of achieving planning permission - it's a sensitive area."
He said the huge contract hinged on a finish date of September 2002. "We're penalised for every day that goes over time."
e-mail: sarah.walsh
@bradford.newsquest.co.uk
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