C#, 267 bytes

using System;using System.Linq;class _{static void Main(){var n=DateTime.Now;var t=n.Month==12?n.Day:0;Console.WriteLine(string.Join(" ",Enumerable.Range(1,25).OrderBy(_=>new Random().Next(-1,1)).Select((d,i)=>(i%5==4?"\r\n":"")+(d<t?$"[ ]":d>t?$"{d}":"[@]"))));}}

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