Missing the final check-in when parole is essentially complete is one of the more frustrating situations that comes up, and the consequences are disproportionate to how close the person was to being fully done.
A blue warrant is a parole violation warrant, and once it is issued, the person is considered an absconder regardless of how little supervision remains. The warrant does not expire and does not get dismissed simply because the original parole term was nearly finished. Until it is resolved, the person carries that warrant wherever they go.
How long someone stays in custody after being picked up on a blue warrant depends on several factors. The original charge and the terms of the parole agreement are the starting points. If the only violation was the missed final check-in with no new criminal conduct involved, the case for a shorter resolution is stronger than if there are additional complications. The parole board and the original sentencing judge both have discretion in determining how to handle it.
In the most straightforward cases where the violation is purely technical, a brief jail stay followed by discharge of the remaining parole obligation is possible. In others, particularly where the supervising officer or the judge takes a harder line, the person could be required to serve additional time before being fully released.
The most practical step is getting an attorney involved immediately to communicate with the parole officer and the court. Framing a single missed final check-in as an administrative failure rather than a deliberate violation is the argument that produces the shortest possible resolution. Every day without legal representation working the problem is another day in custody unnecessarily.