moving parent of a stacked branch.

[David Ingamells]

If the parent branch of a stacked branch is moved to another location 
how does the owner of the stacked branch update his branch to point to 
the new location?

It seems that the .bzr/branch/branch.conf file can be edited, but as far 
as I and the bzr user manual) are concerned this file is internal to 
bazaar and must not be touched by a user.

Thanks in advance,
David.