The difference is simple - the Local license is issued for the firewall gateway IP address, while Central license is issued and assigned to the IP address of the Management SmartCenter. In more practical terms it means you can attach/un-attach/re-attach Central license to/from Gateway(s) as many times as needed as long as IP address of the SmartCenter doesn’t change, thus allowing the same license to be used for different firewall gateways throughout the lifetime of the license or just changing IP addresses for the same gateway.
The Local license is not like that - from the beginning it is being issued by CheckPoint for a specific IP address of the firewall gateway and later if you want to change this IP address you have to ‘move’ the license to the new IP - and you can do it just 6 times, after that you have to buy a new license.