diff --git a/custom_components/optispark/api.py b/custom_components/optispark/api.py
index 8852e1b..2c72b86 100644
--- a/custom_components/optispark/api.py
+++ b/custom_components/optispark/api.py
@@ -92,14 +92,15 @@ def __init__(
         """Sample API Client."""
         self._session = session
 
-    def extra_to_datetime(self, extra):
-        """Corvert unix_time to datetime object."""
-        if 'oldest_dates' in extra and 'newest_dates' in extra:
-            for key in ['oldest_dates', 'newest_dates']:
-                for column in extra[key]:
-                    if extra[key][column] is not None:
-                        extra[key][column] = datetime.fromtimestamp(extra[key][column])
-        return extra
+    #def extra_to_datetime(self, extra):
+    #    """Corvert unix_time to datetime object."""
+    #    if 'oldest_dates' in extra and 'newest_dates' in extra:
+    #        for key in ['oldest_dates', 'newest_dates']:
+    #            for column in extra[key]:
+    #                if extra[key][column] is not None:
+    #                    breakpoint()
+    #                    extra[key][column] = datetime.fromtimestamp(extra[key][column])
+    #    return extra
 
     async def upload_history(self, dynamo_data):
         """Upload historical data to dynamoDB without calculating heat pump profile."""
@@ -111,7 +112,7 @@ async def upload_history(self, dynamo_data):
             url=lambda_url,
             data=payload,
         )
-        extra = self.extra_to_datetime(extra)
+        #extra = self.extra_to_datetime(extra)
         return extra['oldest_dates'], extra['newest_dates']
 
     async def get_data_dates(self, dynamo_data: dict):
@@ -127,7 +128,7 @@ async def get_data_dates(self, dynamo_data: dict):
             url=lambda_url,
             data=payload,
         )
-        extra = self.extra_to_datetime(extra)
+        #extra = self.extra_to_datetime(extra)
         return extra['oldest_dates'], extra['newest_dates']
 
     async def async_get_profile(self, lambda_args: dict):
@@ -152,6 +153,23 @@ async def async_get_profile(self, lambda_args: dict):
             results['projected_percent_savings'] = results['base_cost']/results['optimised_cost']*100 - 100
         return results
 
+    def json_serialisable(self, data):
+        """Convert to compressed bytes so that data can be converted to json."""
+        uncompressed_data = pickle.dumps(data)
+        compressed_data = gzip.compress(uncompressed_data)
+        LOGGER.debug(f'len(uncompressed_data): {len(uncompressed_data)}')
+        LOGGER.debug(f'len(compressed_data): {len(compressed_data)}')
+        base64_string = base64.b64encode(compressed_data).decode('utf-8')
+        return base64_string
+
+    def json_deserialise(self, payload):
+        """Convert from the compressed bytes to original objects."""
+        payload = payload['serialised_payload']
+        payload = base64.b64decode(payload)
+        payload = gzip.decompress(payload)
+        payload = pickle.loads(payload)
+        return payload
+
     async def _api_wrapper(
         self,
         method: str,
@@ -162,17 +180,13 @@ async def _api_wrapper(
         try:
             if 'dynamo_data' in data:
                 data['dynamo_data'] = floats_to_decimal(data['dynamo_data'])
-            uncompressed_data = pickle.dumps(data)
-            compressed_data = gzip.compress(uncompressed_data)
-            LOGGER.debug(f'len(uncompressed_data): {len(uncompressed_data)}')
-            LOGGER.debug(f'len(compressed_data): {len(compressed_data)}')
-            base64_string = base64.b64encode(compressed_data).decode('utf-8')
+            data = self.json_serialisable(data)
 
             async with async_timeout.timeout(40):
                 response = await self._session.request(
                     method=method,
                     url=url,
-                    json=base64_string,
+                    json=data,
                 )
                 if response.status in (401, 403):
                     raise OptisparkApiClientAuthenticationError(
@@ -184,7 +198,8 @@ async def _api_wrapper(
                     raise OptisparkApiClientCommunicationError(
                         '502 Bad Gateway - check payload')
                 response.raise_for_status()
-                return await response.json()
+                payload = await response.json()
+                return self.json_deserialise(payload)
 
         except asyncio.TimeoutError as exception:
             LOGGER.error(traceback.format_exc())
diff --git a/custom_components/optispark/const.py b/custom_components/optispark/const.py
index 2fe440f..a000448 100644
--- a/custom_components/optispark/const.py
+++ b/custom_components/optispark/const.py
@@ -5,7 +5,7 @@
 
 NAME = "Optispark"
 DOMAIN = "optispark"
-VERSION = "0.1.8"
+VERSION = "0.1.9"
 ATTRIBUTION = "Data provided by http://jsonplaceholder.typicode.com/"
 
 LAMBDA_TEMP = 'temps'
@@ -24,7 +24,7 @@
 LAMBDA_INITIAL_INTERNAL_TEMP = 'initial_internal_temp'
 
 HISTORY_DAYS = 28  # the number of days initially required by our algorithm
-DYNAMO_HISTORY_DAYS = 365*5
+DYNAMO_HISTORY_DAYS = 365*2
 MAX_UPLOAD_HISTORY_READINGS = 5000
 DATABASE_COLUMN_SENSOR_HEAT_PUMP_POWER = 'heat_pump_power'
 DATABASE_COLUMN_SENSOR_EXTERNAL_TEMPERATURE = 'external_temperature'
diff --git a/custom_components/optispark/coordinator.py b/custom_components/optispark/coordinator.py
index 5b3ca46..6512cd3 100644
--- a/custom_components/optispark/coordinator.py
+++ b/custom_components/optispark/coordinator.py
@@ -351,7 +351,7 @@ def get_missing_new_histories_states(self, history_states, column):
         return history_states[idx_bound+1:]
 
     async def upload_new_history(self):
-        """Upload section of new history states that are older than anything in dynamo.
+        """Upload section of new history states that are newer than anything in dynamo.
 
         self.dynamo_dates is updated so that if this function is called again a new section will be
         uploaded.
diff --git a/custom_components/optispark/manifest.json b/custom_components/optispark/manifest.json
index 7c81e27..b864ab1 100644
--- a/custom_components/optispark/manifest.json
+++ b/custom_components/optispark/manifest.json
@@ -11,5 +11,5 @@
   "iot_class": "cloud_polling",
   "issue_tracker": "https://github.com/Big-Tree/HomeAssistant-OptiSpark/issues",
   "requirements": ["geopy==2.4.1"],
-  "version": "0.1.8"
+  "version": "0.1.9"
 }