When The Secret Keeper Dies

This is from http://www.jkrowling.com
To open the “F.A.Q” section, click on the little cluster of paper clips.

The most frequently asked question was:
“What happens to a secret when the secret keeper dies?”

JKR’s answer was:
“When a secret keeper dies, their secret dies with them,
or, to put it another way, the status of their secret will
remain the way it was at the moment of their death.
Everybody in whom they confided will continue to know
the hidden information, but nobody else….”

My question:
How would this work at HQ, at Grimold Place?
If Dumbledore dies, can a new member of the Order go there?
If it is no longer HQ, can Harry bring friends over?
Can Narcissa remember the place from her childhood and visit?

I would think that Kreacher would know all of the secrets at the HQ, ya kno.

Just wondering what will happen with Snape knowing where the HQs are for Order of the Phoenix? I'm undecided as to which side he is on, so if it's actually the bad side then there's some big consequences for the Order. Also, did we ever get confirmation that the Order moved back into 12 Grimmauld Place after it became evident that Sirius had done his will for it properly. If they have been using it since then they might have to move it anyway and get a new secret keeper for their new place.

I've changed my mind. Until the members of the Order find out that Snape is still with them, they will take precautions. Also, the place still has a bunch of elaborate magical protections left over from the Blacks. I think they can still use it to some extent.