TUBE users say they fear a 12-day closure of the Central line's Hainault loop will 'cause havoc' for commuters.
The line will be closed from October 24 to November 4 between Grange Hill and Newbury Park on weekdays and Woodford and Leytonstone at weekends.
Replacement bus services will be laid on while tracks, drainage, points and crossings are replaced.
Transport for London (TfL) claims closing the loop in a continual block over half term will speed up work, saving more than £2m by avoiding a string of individual weekend closures.
But regular travellers have criticised the decision to close on weekdays, rather than completing the work on weekends and overnight.
Tube user Jill Spero, 70, of Green Lane, Chigwell, said: "I think it's a mad idea. It's absolutely ludicrous. How on earth are people supposed to cope?
"How many people nowadays are going away for half term? Not everybody can afford to pack up.
"They don't close other lines, they do overnight work. I don't see why they can't do that here."
Ruth Montefiore, of New Barns Way, has spent more than a decade campaigning for a better service on the loop.
The 62-year-old said she feared replacement bus services would not be an adequate alternative.
"It will certainly cause havoc. They could have waited until the Christmas holidays," she added.
But Alf Oliver, 85, said he and his neighbours in Chigwell Park would enjoy the break from their daily battle with commuters, who park in the residential road before heading for the station.
He said: "It will certainly be a break, no two ways about it. It will take the pressure off.
"But as soon as it opens up they'll all be back."
Neighbour Patricia Sullivan, 70, said the closure was unlikely to improve the situation - because builders working on a site in the High Road had also begun parking their vehicles in the road.
"I really don't know if that's going to make much difference at all. We do have an awful lot of builders' vans," she said.
"I have had some near misses when I've tried to back out and I can't see. It's dangerous. The only respite we have are Saturdays and Sundays.
"It'll all come back again. It never changes."
George McInulty, London Underground programme director of infrastructure, said: "This upgrade work is essential to make the Central line as reliable and as safe as possible.
"We apologise to anyone affected by this closure but carrying the work out during the quieter school holiday period is by far the least disruptive way to do this."
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