Changing the name of a Facebook Page
Is it possible to change the name of a fan page with just over 450 members?
The one member of the radio show is leaving in the new year and the name needs to be edited and his name removed.
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If the fan page is built on his name then it comes under the category of "Artist, band or public figure"; therefor you can't expect people who joined the page for him to be in it for another person, because they are his fans not the new guy fans.
Personally I'd feel offended if somebody did something like that to me "it is like breaking a contract", and knowing that you are running a radio station; which means you have an image to look after, and you don't want to lose listeners for 450m fan page.
Another solution that you can use is to utilize his page to your benefit, I mean you can advertise for the new comer using the old page, also keep your station updating it, maybe start a new competition on your new fan page which require joining to enter it.
Personally, I think it is better to build you page under the "Local business and places" category and not do the same mistake again. And for the radio show host, have people following him on your radio fan page not his.