Archive data in Firebase 1.x

archive_data.js

var Firebase = require('firebase');
var rootRef = new Firebase("https://<YOUR-FIREBASE-APP>.firebaseio.com/");
var archiveRef = rootRef.child('path/to/archive');
var dataRef = rootRef.child('path/to/data');
var archiveTimestamp = Date.now() - 3600; // everything older than an hour

dataRef.orderByChild('<date field>').endAt(archiveTimestamp).once('value', function(snap) {
    snap.forEach(function(childSnap) {
         archiveRef.child( childSnap.key() ).set( childSnap.val(), function(err) {
              if( err ) { console.error(err); }
              else { childSnap.ref().remove(); }
         });      
    });
});