diff --git a/pvt_model/argparser.py b/pvt_model/argparser.py
index 98d6acb..be4bce3 100644
--- a/pvt_model/argparser.py
+++ b/pvt_model/argparser.py
@@ -355,7 +355,7 @@ def parse_args(args) -> argparse.Namespace:
         "--months",
         "-m",
         help="The number of months for which to run the simulation. Default is 12.",
-        default=12,
+        default=None,
         type=int,
     )
     parser.add_argument(
diff --git a/pvt_model/pvt_system_model/convergent_solver.py b/pvt_model/pvt_system_model/convergent_solver.py
index 308f649..402f932 100644
--- a/pvt_model/pvt_system_model/convergent_solver.py
+++ b/pvt_model/pvt_system_model/convergent_solver.py
@@ -73,7 +73,7 @@ def _calculate_vector_difference(
         ) from None
 
     # Take the sum of the values in this vector to avoid sign issues and return the sum.
-    return sum({abs(value) for value in diff_vector})
+    return sum([abs(value) for value in diff_vector])
 
 
 def solve_temperature_vector_convergence_method(
diff --git a/pvt_model/pvt_system_model/runs/decoupled.py b/pvt_model/pvt_system_model/runs/decoupled.py
index 196a83e..24b7f1a 100644
--- a/pvt_model/pvt_system_model/runs/decoupled.py
+++ b/pvt_model/pvt_system_model/runs/decoupled.py
@@ -143,11 +143,7 @@ def decoupled_dynamic_run(
         )
 
     # Determine the number of minutes, days, and months for which to run the simulation.
-    num_months = (
-        (initial_month if initial_month is not None else 1)
-        - 1
-        + (months if months is not None else 0)
-    )  # [months]
+    num_months = months if months is not None else 0  # [months]
     start_month = (
         initial_month
         if 1 <= initial_month <= 12
diff --git a/system_data/london_dyamic_decoupled/solar_irradiance_profiles/december_lower_bound_test_jump.json b/system_data/london_dyamic_decoupled/solar_irradiance_profiles/december_lower_bound_test_jump.json
new file mode 100644
index 0000000..3d340aa
--- /dev/null
+++ b/system_data/london_dyamic_decoupled/solar_irradiance_profiles/december_lower_bound_test_jump.json
@@ -0,0 +1,102 @@
+{
+    "12:00:00": 30,
+    "12:00:10": 30,
+    "12:00:20": 30,
+    "12:00:30": 30,
+    "12:00:40": 30,
+    "12:00:50": 30,
+    "12:01:00": 30,
+    "12:01:10": 30,
+    "12:01:20": 30,
+    "12:01:30": 30,
+    "12:01:40": 30,
+    "12:01:50": 30,
+    "12:02:00": 30,
+    "12:02:10": 30,
+    "12:02:20": 30,
+    "12:02:30": 30,
+    "12:02:40": 30,
+    "12:02:50": 30,
+    "12:03:00": 30,
+    "12:03:10": 30,
+    "12:03:20": 30,
+    "12:03:30": 30,
+    "12:03:40": 30,
+    "12:03:50": 30,
+    "12:04:00": 30,
+    "12:04:10": 30,
+    "12:04:20": 30,
+    "12:04:30": 30,
+    "12:04:40": 30,
+    "12:04:50": 30,
+    "12:05:00": 30,
+    "12:05:10": 30,
+    "12:05:20": 30,
+    "12:05:30": 30,
+    "12:05:40": 30,
+    "12:05:50": 30,
+    "12:06:00": 30,
+    "12:06:10": 30,
+    "12:06:20": 30,
+    "12:06:30": 30,
+    "12:06:40": 30,
+    "12:06:50": 30,
+    "12:07:00": 30,
+    "12:07:10": 30,
+    "12:07:20": 30,
+    "12:07:30": 30,
+    "12:07:40": 30,
+    "12:07:50": 30,
+    "12:08:00": 30,
+    "12:08:10": 30,
+    "12:08:20": 30,
+    "12:08:30": 30,
+    "12:08:40": 30,
+    "12:08:50": 30,
+    "12:09:00": 30,
+    "12:09:10": 30,
+    "12:09:20": 30,
+    "12:09:30": 30,
+    "12:09:40": 30,
+    "12:09:50": 30,
+    "12:10:00": 29.892421859707724,
+    "12:10:10": 30.515839779277712,
+    "12:10:20": 29.30998989332727,
+    "12:10:30": 29.933168128960574,
+    "12:10:40": 30.556346364593878,
+    "12:10:50": 875.6912551315664,
+    "12:11:00": 874.4851655616792,
+    "12:11:10": 876.3276159837227,
+    "12:11:20": 872.0732261058417,
+    "12:11:30": 873.3061602766485,
+    "12:11:40": 873.9295781962185,
+    "12:11:50": 871.5046958077947,
+    "12:12:00": 872.1285930952383,
+    "12:12:10": 875.1893569679448,
+    "12:12:20": 881.9115326589337,
+    "12:12:30": 888.0229936790018,
+    "12:12:40": 891.6937531708187,
+    "12:12:50": 891.0978989039786,
+    "12:13:00": 897.2095996079835,
+    "12:13:10": 897.83253815968,
+    "12:13:20": 898.4557163953133,
+    "12:13:30": 894.8110824526058,
+    "12:13:40": 894.8245047530655,
+    "12:13:50": 892.3984239449578,
+    "12:14:00": 886.3145265776195,
+    "12:14:10": 882.0598970158018,
+    "12:14:20": 877.8047880861104,
+    "12:14:30": 877.8189294383806,
+    "12:14:40": 879.052103293124,
+    "12:14:50": 886.9918733829655,
+    "12:15:00": 901.6403968633362,
+    "12:15:10": 906.531626961247,
+    "12:15:20": 907.1552845647539,
+    "12:15:30": 907.7789421682606,
+    "12:15:40": 907.7911660490365,
+    "12:15:50": 906.5850764791494,
+    "12:16:00": 906.5999368832299,
+    "12:16:10": 905.3936076294059,
+    "12:16:20": 906.6267814841494,
+    "12:16:30": 912.7377631363441
+}
\ No newline at end of file
diff --git a/system_data/london_dyamic_decoupled/temperature_profiles/december_lower_bound_test_jump.json b/system_data/london_dyamic_decoupled/temperature_profiles/december_lower_bound_test_jump.json
new file mode 100644
index 0000000..378a857
--- /dev/null
+++ b/system_data/london_dyamic_decoupled/temperature_profiles/december_lower_bound_test_jump.json
@@ -0,0 +1,102 @@
+{
+    "12:00:00": 18,
+    "12:00:10": 18,
+    "12:00:20": 18,
+    "12:00:30": 18,
+    "12:00:40": 18,
+    "12:00:50": 18,
+    "12:01:00": 18,
+    "12:01:10": 18,
+    "12:01:20": 18,
+    "12:01:30": 18,
+    "12:01:40": 18,
+    "12:01:50": 18,
+    "12:02:00": 18,
+    "12:02:10": 18,
+    "12:02:20": 18,
+    "12:02:30": 18,
+    "12:02:40": 18,
+    "12:02:50": 18,
+    "12:03:00": 18,
+    "12:03:10": 18,
+    "12:03:20": 18,
+    "12:03:30": 18,
+    "12:03:40": 18,
+    "12:03:50": 18,
+    "12:04:00": 18,
+    "12:04:10": 18,
+    "12:04:20": 18,
+    "12:04:30": 18,
+    "12:04:40": 18,
+    "12:04:50": 18,
+    "12:05:00": 18,
+    "12:05:10": 18,
+    "12:05:20": 18,
+    "12:05:30": 18,
+    "12:05:40": 18,
+    "12:05:50": 18,
+    "12:06:00": 18,
+    "12:06:10": 18,
+    "12:06:20": 18,
+    "12:06:30": 18,
+    "12:06:40": 18,
+    "12:06:50": 18,
+    "12:07:00": 18,
+    "12:07:10": 18,
+    "12:07:20": 18,
+    "12:07:30": 18,
+    "12:07:40": 18,
+    "12:07:50": 18,
+    "12:08:00": 18,
+    "12:08:10": 18,
+    "12:08:20": 18,
+    "12:08:30": 18,
+    "12:08:40": 18,
+    "12:08:50": 18,
+    "12:09:00": 18,
+    "12:09:10": 18,
+    "12:09:20": 18,
+    "12:09:30": 18,
+    "12:09:40": 18,
+    "12:09:50": 18,
+    "12:10:00": 17.93846153846154,
+    "12:10:10": 17.93846153846154,
+    "12:10:20": 17.972649572649573,
+    "12:10:30": 18.045299145299147,
+    "12:10:40": 18.01111111111111,
+    "12:10:50": 18.032478632478632,
+    "12:11:00": 18.032478632478632,
+    "12:11:10": 18.0025641025641,
+    "12:11:20": 17.908547008547007,
+    "12:11:30": 17.844444444444445,
+    "12:11:40": 17.887179487179488,
+    "12:11:50": 17.904273504273505,
+    "12:12:00": 18.058119658119658,
+    "12:12:10": 18.207692307692305,
+    "12:12:20": 18.352991452991454,
+    "12:12:30": 18.476923076923075,
+    "12:12:40": 18.545299145299143,
+    "12:12:50": 18.592307692307692,
+    "12:13:00": 18.54957264957265,
+    "12:13:10": 18.515384615384615,
+    "12:13:20": 18.472649572649573,
+    "12:13:30": 18.412820512820513,
+    "12:13:40": 18.357264957264956,
+    "12:13:50": 18.34444444444444,
+    "12:14:00": 18.335897435897436,
+    "12:14:10": 18.284615384615385,
+    "12:14:20": 18.284615384615385,
+    "12:14:30": 18.425641025641024,
+    "12:14:40": 18.472649572649573,
+    "12:14:50": 18.519658119658118,
+    "12:15:00": 18.506837606837607,
+    "12:15:10": 18.532478632478632,
+    "12:15:20": 18.43846153846154,
+    "12:15:30": 18.374358974358973,
+    "12:15:40": 18.459829059829058,
+    "12:15:50": 18.532478632478632,
+    "12:16:00": 18.605128205128203,
+    "12:16:10": 18.746153846153845,
+    "12:16:20": 18.88290598290598,
+    "12:16:30": 18.94273504273504
+}
\ No newline at end of file