I was only commenting on the UK 
 
39 does sound high and I thought hot air expanded. 
 
Let me know if you find out any more on if it's correct to over inflate in high temperatures. I would of thought that it's the other way round if anything. 
 
The "C" is not for cargo. It's a load rating. 
		
		
		
		
		
		
		
	
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