not sure about it but if screenshot was taken today the 20 May... 8w 4d put your arrival in this kingdom the 22 March... at 8w 6d, the 22 may, it will be 2 month...
maybe the message system use 4 week for the condition but the game engine use the real 2 month delay...
If you are able to move to a other kingdom the 22 or 23 May, it will confirm my theory...
Problem like this appear all the time in software due to poor communication between the various programmer... the guy who have made the code for the condition use 8 week for 2 month but the one who wrote the code for execute the moving use the real 2 month calendar...
I have found Similar coding mistake in a other game with the "K" unit... when buying something, it was metric unit... 1K = 1000 gold... but when selling, it was binary unit... 1k = 1024 gold... buying and selling a lot of time the same object was leading to a increase of your gold reserve...