Swap tail fix

Author: springfall2008

apps/predbat/plan.py

@@ -2288,7 +2288,7 @@ def optimise_swap_export(self, record_charge_windows, record_export_windows, deb
                 swapped = False
 
                 for window_n_target in range(record_export_windows - 1, 0, -1):
-                    previous_end = 0
+                    previous_end_target = 0
                     if window_n_target > 0:
                         previous_end_target = self.export_window_best[window_n_target - 1]["end"]
                     window_start_target = self.export_window_best[window_n_target]["start"]
@@ -2351,6 +2351,10 @@ def optimise_swap_export(self, record_charge_windows, record_export_windows, deb
                             # Don't swap if the windows are the same
                             continue
 
+                        if export_limit < 100 and export_limit_target < 100 and window_length < window_length_target:
+                            # Don't swap if we move a smaller window later
+                            continue
+
                         if export_limit < 99 and window_length <= window_length_target:
                             # Don't optimise a charge window that hits an export window if this is disallowed
                             if not self.calculate_export_oncharge:

apps/predbat/predbat.py

@@ -36,7 +36,7 @@
 import requests
 import asyncio
 
-THIS_VERSION = "v8.20.2"
+THIS_VERSION = "v8.20.3"
 
 # fmt: off
 PREDBAT_FILES = ["predbat.py", "config.py", "prediction.py", "gecloud.py","utils.py", "inverter.py", "ha.py", "download.py", "unit_test.py", "web.py", "predheat.py", "futurerate.py", "octopus.py", "solcast.py","execute.py", "plan.py", "fetch.py", "output.py", "userinterface.py", "energydataservice.py", "alertfeed.py", "compare.py", "db_manager.py", "db_engine.py"]