Calculating Mythic Dragon Spell Resistance

[Illius]

I am currently stating up a mythic dragon in an age category that is not listed in the Mythic Adventures Bestiary. My problem arises when calculating spell resistance.
The dragon entry in the bestiary tells me that a dragon's spell resistance is equal to 11+ it's CR, and when applying the mythic subtype to a monster , mythic ranks increase a monsters SR by 1 for each rank. Yet, when I examine the entries for mythic dragons in mythic adventures their SR is equal to 11+ CR, when the mythic subtype says it ought to be higher. SO my question is does a dragon's innate SR trump the mythic rules for additional Sr?

Here are my calculations:

Dragon SR = 11 + CR (CR is 16 for an Ancient Black Dragon)

Base SR = 27 (as listed in it's bestiary entry)

Then I apply 8 mythic ranks, making it's new CR 20, and thus making it's new SR 31 (by the Dragon SR equation).

Now because the mythic subtype adds additional SR based on it's mythic rank, I add an additional 8 SR:

New Dragon SR = 11 + 20 + 8 = 39

Yet when I look at all the SR listed in mythic adventures, all the dragons have SR = 11 + CR. Have I missed something or was the additional SR not applied in Mythic Adventures? Any explanation would be helpful.

Thank you in advance,

Illius

[KainPen]

It is Typo's in mythic adventures book left over the play test that was not edited out, but as is there is no clear answer.
see this tread It not just dragons that are effective by this typo or typo if all the example creatures are wrong. My guess is the creatures are correct and the the subtype information is incorrect. the SR more then likely just increase by whatever the cr is increased by adding 1/2 mythic rank.

[Illius]

Thanks, I have looked at various monsters in my Wrath of the Righteous books which seem to follow the rules as stated in mythic adventures, which just adds to the confusion.