128 The translation “day is breaking” for ῥμέρα γίνεται (hēmera ginetai) in this verse is given by ῥμέρα 1.a.
129 On the term translated “magistrates,” see στρατηγός 1. These city leaders were properly called duoviri, but were popularly known as praetors (στρατηγοί, stratēgoi). They were the chief officials of Philippi. The text leaves the impression that they came to the decision to release Paul and Silas independently. God was at work everywhere.
130 On the term ῥαβδοῦχος (rhabdouchos) see The term was used of the Roman lictor and roughly corresponds to contemporary English “constable, policeman.”

In other versions

But when it was day, the magistrates sent the police, saying, “Let those men go.”

When it was daylight, the magistrates sent their officers to the jailer with the order: “Release those men.”

When daylight came, the chief magistrates sent the police to say, “Release those men.”

The next morning the city officials sent the police to tell the jailer, “Let those men go!”

And when it was day, the chief magistrates sent the police officers, saying, “Release those men.”

And when it was day, the magistrates sent the serjeants, saying, Let those men go.

Public Domain