President Trump shortened the sentences of thousands of prisoners by signing the First Step Act days before Christmas. But one week later, inmates and their frustrated families say they are afraid the gift won’t be delivered in time to hasten release dates.

Silence from the Federal Bureau of Prisons is creating fear that foot-dragging will eat into reductions mandated by Trump’s most significant bipartisan policy achievement. The new law gives many prisoners an extra seven days off their sentences for each year of good behavior, but it’s unclear when authorities will make the calculations.