Dragon becoming a Dracolich

[Jaxom]

In a game I'm currently running the players witnessed the ritual and death of a dragon becoming a dracolich.
How long of a period is required for the dragon's soul to go to its phlactery after it dies before it can re-inhabit it's now dead body?

 

[Mr Fidgit]

the FRCS says, "immediately", but if the players are on hand (and are going to do something about this new nastiness), you could impose a 2 round time limit (one for the soul to transfer to the phylactery, and one to go from the phylactery to the body).

(btw, the only 'times' mentioned in the book are if a dracolich can't posses its own body, then it has to transform its new body to look like the old one (after making checks to posses it), which is 2d4 days)