Quote Originally Posted by mattie_p View Post
A 165: No. Lacking rules text on Ex-Ur-Priests (see Ex-Bards, Barbarians, Monks, Druids, Paladins for examples), and defaulting to the DMG rule on Prestige classes (must meet criteria for first level only) an Ur-Priest does not need to remain evil.

A 166: Correct. Without an Ex-X section, other notes on the topic, and outside of Complete Warrior/Arcane. Otherwise, an Ur-Priest would be useless, as it grants the ability to cast divine spells while requiring the character to forever forsake previous divine casting ability.
A 165 Dispute

Complete arcane [p17] and Complete warrior [p16] state if a character doen't met the prerequisite of a prestige class anymore he loses all class benefits of the PRC, retaining only HDs, BaB and saves. While the sentence in CW falls under the "martial prestige classes" section, leading to believe it applies only to the classes presented in that book, the CA one is in "picking a prestige clsss", and nothing hints that it doesn't apply as a general rule.

An Ur-priest who is no logner evil loses all benefits of the Ur-Priest PRC except for those noted, so cannot advance "spellcasting" with other PRCs.

A 166

Debtable. RAW seems to suggest you can still advance a PRC you did qualify for even if you no longer meet the prerequisites. Obviously you are only advancing BaB, saves and HDs (See A 165).