Ms Wilkinson, a former charity worker, began legal action in an attempt to force Anjum to reveal Atiya's whereabouts. A number of judges have examined the case over the past three years and have imposed a series of jail terms after concluding that Anjum was in contempt.
He was serving a 12-month term imposed in October and would have been eligible for release on parole in April. Mr Justice Holman - who heard evidence at a High Court hearing in London - said that 12-month term should be cut to 10 months, following Atiya's discovery.
Lawyers said that would make Anjum eligible for release on parole in March.
Judges have heard that Anjum's "on-off" relationship with Ms Wilkinson ended in 2008 and that Atiya vanished after going to stay with her father the following year.
Anjum had said he was taking Atiya to Southport, Lancashire. Instead he took her to Lahore, Pakistan and told Ms Wilkinson she was "never going to see Atiya again".