Undead and age related stat modifiers

[Xexyz]

Are there any rules/guidelines for what happens when a creature in an advanced age category acquires an undead template (such as lich or vampire)? Do they keep the stat adjustments due to age or do they go away?

[Starglim]

Apply the effects of the template to the base creature. A vampire, for example, adds 6 to the Strength score that the creature had immediately before becoming a vampire.

Unless the template says that it reverses aging adjustments, they remain.

[Aaron Burr]

Another question is which if any of the stat modifiers do undead get who where middle aged when they became undead? Just the increases to mental scores or also the decreases in phyiscal scores or neither?

[Starglim]

If they are undead templates, see above. If they have a standard monster stat block, by RAW none, though a GM should of course alter the physical abilities of an undead that's missing limbs or the like, or is child-sized (edit: which would presumably give it the Young template).