CHICAGO (STMW) — Thirty-four days have passed since Dennis Hastert reported to a southeast Minnesota prison to begin serving his 15-month sentence.

But after initially predicting the former speaker of the U.S. House of Representatives would go free on July 23, 2017, the Federal Bureau of Prisons now apparently expects Hastert to spend a little more time behind bars.

Prison officials recently pushed Hastert’s projected release date back to Aug. 16, 2017, potentially adding another 24 days to Hastert’s stay at the Rochester Federal Medical Center.

Authorities won’t explain the change. BOP spokesman Justin Long said the reason for the adjustment “is not public information,” and Hastert’s legal team declined to comment.

Jeffrey Cramer, a former federal prosecutor who is now the managing director of Berkeley Research Group, said an inmate’s release date could be pushed back if the inmate gets into trouble in prison, but he also said, “I can’t fathom that Denny Hastert got in some type of trouble.”

More likely, Cramer said, is that the change is the result of something as “benign” as a miscalculation in the original date. And even though it looks now like Hastert will spend more time in prison, that could change as he nears the end of his sentence.

“There’s always wiggle room,” Cramer said.

U.S. District Judge Thomas M. Durkin sentenced Hastert, 74, to 15 months in prison earlier this year for breaking the law while trying to conceal his past sexual abuse of teenage boys. Hastert was hit with a bombshell criminal indictment in May 2015 that accused him of illegally structuring bank withdrawals and lying to the FBI.

He pleaded guilty to the structuring, and acknowledged the lying, last October. Then, during his sentencing hearing last April, he admitted to the judge that he sexually abused children in the 1970s. However, as the judge noted, prosecutors could not charge Hastert for the sexual abuse because the statute of limitations had long run out.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)