diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 7fcd6dc..98a45b5 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -25,4 +25,4 @@ jobs:
     - name: Build
       run: dotnet build --no-restore
     - name: Test
-      run: dotnet test --no-build --verbosity normal
+      run: dotnet test --no-build --verbosity normal
\ No newline at end of file
diff --git a/Controllers/TJController.cs b/Controllers/TJController.cs
index 3c121b9..1912bef 100644
--- a/Controllers/TJController.cs
+++ b/Controllers/TJController.cs
@@ -9,14 +9,13 @@ record TJRequest(int Period, int Year, int Duration);
 [ApiController]
 public class TJController : ControllerBase
 {
-    [HttpGet("{period:int}/{year:int}/{duration:int}")]
-    public IActionResult TJ(int period, int year, int duration)
+    [HttpGet("{period:int}/{year:int}/{duration:int?}")]
+    public IActionResult TJ(int period, int year, int duration = 0)
     {
         TJRequest req = new(period, year, duration);
         return GenerateResponse(req);
     }
 
-
     private bool ValidateRequest(TJRequest req, out ObjectResult error)
     {
         error = BadRequest(new ErrorMessage("This shouldn't appear! Aamuja."));
@@ -52,7 +51,7 @@ private ObjectResult GenerateResponse(TJRequest req)
             // Assume it's the 21 century
             year += 2000;
 
-        TJ tj = TJGenerator.GenerateTJ(req.Period == 1, year, req.Duration);
+        TJ tj = TJGenerator.GenerateTJ(req.Period, year, req.Duration);
         return Ok(tj);
     }
 }
\ No newline at end of file
diff --git a/Models/TJ.cs b/Models/TJ.cs
index 0f730bd..1b413c9 100644
--- a/Models/TJ.cs
+++ b/Models/TJ.cs
@@ -1,8 +1,10 @@
 namespace TJ_API.Models;
 
 public record TJ(
-    int Days,
+    double Days,
     double Weeks,
     double Months,
-    double Seconds
+    double Seconds,
+    long StartDate,
+    long ReturnDate
 );
\ No newline at end of file
diff --git a/Services/TJGenerator.cs b/Services/TJGenerator.cs
index a1cb407..b546c17 100644
--- a/Services/TJGenerator.cs
+++ b/Services/TJGenerator.cs
@@ -1,30 +1,67 @@
 using TJ_API.Models;
+using TJ_API.Services;
 
 namespace TJ_API.Services;
 
 public static class TJGenerator
 {
-    public static TJ GenerateTJ(bool firstPeriod, int year, int duration)
+    /// <summary>
+    /// Arrival patches mapped with their starting dates.
+    /// </summary>
+    private static readonly Dictionary<string, DateTime> StartingDates = new()
     {
-        DateTime beginningDate;
-        if (firstPeriod)
-        {
-            // Assume first period starts January 6th
-            beginningDate = new(year, 1, 6);
-        }
-        else
-        {
-            // Assume second period starts July 7th
-            beginningDate = new(year, 7, 7);
-        }
+        {"1/2016", Utility.GenerateFinnishDate(2016, 1, 4)},
+        {"2/2016", Utility.GenerateFinnishDate(2016, 7, 4)},
+        {"1/2017", Utility.GenerateFinnishDate(2017, 1, 2)},
+        {"2/2017", Utility.GenerateFinnishDate(2017, 7, 3)},
+        {"1/2018", Utility.GenerateFinnishDate(2018, 1, 8)},
+        {"2/2018", Utility.GenerateFinnishDate(2018, 7, 9)},
+        {"1/2019", Utility.GenerateFinnishDate(2019, 1, 7)},
+        {"2/2019", Utility.GenerateFinnishDate(2019, 7, 8)},
+        {"1/2020", Utility.GenerateFinnishDate(2020, 1, 6)},
+        {"2/2020", Utility.GenerateFinnishDate(2020, 7, 6)},
+        {"1/2021", Utility.GenerateFinnishDate(2021, 1, 4)},
+        {"2/2021", Utility.GenerateFinnishDate(2021, 7, 5)},
+        {"1/2022", Utility.GenerateFinnishDate(2022, 1, 3)},
+        {"2/2022", Utility.GenerateFinnishDate(2022, 7, 4)},
+        {"1/2023", Utility.GenerateFinnishDate(2023, 1, 2)},
+        {"2/2023", Utility.GenerateFinnishDate(2023, 7, 3)},
+        {"1/2024", Utility.GenerateFinnishDate(2024, 1, 8)},
+        {"2/2024", Utility.GenerateFinnishDate(2024, 7, 8)},
+        {"1/2025", Utility.GenerateFinnishDate(2025, 1, 6)},
+        {"2/2025", Utility.GenerateFinnishDate(2025, 7, 7)},
+        {"1/2026", Utility.GenerateFinnishDate(2026, 1, 5)},
+        {"2/2026", Utility.GenerateFinnishDate(2026, 7, 6)},
+    };
+
+    private static string GenerateArrivalPatch(int period, int year)
+    {
+        return $"{period}/{year}";
+    }
+
+    public static TJ GenerateTJ(int period, int year, int duration)
+    {
+        if (!StartingDates.TryGetValue(GenerateArrivalPatch(period, year), out DateTime beginningDate))
+            if (period == 1)
+            {
+                // Assume first period starts January 6th
+                beginningDate = new(year, 1, 6);
+            }
+            else
+            {
+                // Assume second period starts July 7th
+                beginningDate = new(year, 7, 7);
+            }
         DateTime endingDate = beginningDate.AddDays(duration);
         TimeSpan tjSpan = endingDate - DateTime.Now;
 
         return new TJ(
-            Days: tjSpan.Days,
-            Weeks: Math.Round((double)tjSpan.Days / 7f, 2),
-            Months: Math.Round((double)tjSpan.Days / 30f, 2),
-            Seconds: Math.Ceiling(tjSpan.TotalSeconds)
+            Days: Math.Round(tjSpan.TotalDays, 2),
+            Weeks: Math.Round(tjSpan.TotalDays / 7f, 2),
+            Months: Math.Round(tjSpan.TotalDays / 30f, 2),
+            Seconds: Math.Round(tjSpan.TotalSeconds, 1),
+            StartDate: Utility.GetUnixTimestamp(beginningDate),
+            ReturnDate: Utility.GetUnixTimestamp(endingDate)
         );
     }
 }
diff --git a/Services/Utility.cs b/Services/Utility.cs
index bb81f96..758fb6a 100644
--- a/Services/Utility.cs
+++ b/Services/Utility.cs
@@ -2,6 +2,17 @@ namespace TJ_API.Services;
 
 public static class Utility
 {
+    private static readonly TimeZoneInfo FinnishTimeZone = TimeZoneInfo.FindSystemTimeZoneById("FLE Standard Time");
+
+    /// <summary>
+    /// Generates a DateTime with the Finnish timezone
+    /// </summary>
+    public static DateTime GenerateFinnishDate(int year, int month, int day)
+    {
+        DateTime date = new(year, month, day);
+        return TimeZoneInfo.ConvertTimeFromUtc(date, FinnishTimeZone);
+    }
+
     /// <summary>
     /// Calculates the length of an integer.
     /// Ex. 12345 -> 5
@@ -11,4 +22,12 @@ public static int IntegerLength(int num)
         int abs = (num == int.MinValue) ? int.MaxValue : Math.Abs(num);
         return (num == 0) ? 1 : (int)Math.Floor(Math.Log10(abs)) + 1;
     }
+
+    /// <summary>
+    /// Converts given DateTime into a Unix timestamp long integer
+    /// </summary>
+    public static long GetUnixTimestamp(DateTime date)
+    {
+        return ((DateTimeOffset)date).ToUnixTimeSeconds();
+    }
 }
\ No newline at end of file