Interesting. I'm leaning towards thinking M must have received it as a gift from someone important.
If there's still a suggestion that "Skyfall" may also be the name of a former MI6 operation M was involved in, perhaps the bulldog is also linked to someone from Bond's past in some form.
It is so curious that the word "Skyfall" comes up in that evaluation and prompts such a reaction in Bond. Such an unusual word (an invented word) could not coincidentally be the name of both a mission and Bond’s old home.
But I think it must be or that MI-6 know that’s what Silva’s plan is called somehow or they call Sliva's methods "Skyfall". We know that part of what Silva does is spread panic when there is no reason for panic. That’s how he has acquired his island. Like a multivalent Chicken Licken.
Therefore, a connection between Bond’s past and this mission seems the only explanation. I also think it must be important that...
– the filmmakers have gone to so much trouble to have this final confrontation between them take place there – why?