NIS 2010 Licence Renewal prices

My NIS 2010 licence is coming up for renewal in a couple of weeks time.  I launched NIS 2010 and clicked Express Renewal, which took me to Symantec's website where it quoted a one-year renewal price of £54.99.

 

Then, I went to Symantec's Online Store website, where NIS 2010 was priced at £49.99 !

 

Then, I went to Amazon's website, where NIS 2010 is priced at £32.

 

Come on Symantec, what is going on here?  Two different prices for the same product on your own websites!  Also, how can Amazon sell it much cheaper than Symantec?

 

Presumably, if I bought another NIS 2010 from Amazon, clicked Express Renewal on my existing NIS 2010, and entered the product key from the Amazon one, would I then get a full year's renewal ? (or would I have to uninstall my existing NIS 2010 and install the Amazon one ?).

 

Regards.