A spell-warding creature's quick and rebuild rules are the same.

Rebuild Rules: Defensive Abilities gains the spell shield defensive ability described below; SR gains SR equal to 16 + the spell-warding creature's CR.

Spell Shield (Su) The spell-warding creature is surrounded by a shimmering field of force that grants it a +4 shield bonus to AC. This ability counts as a force effect. Whenever a spell fails to overcome the spell-warding creature's spell resistance, the shield bonus granted by this ability is increased by the spell level of that spell for 1 round, to a maximum shield bonus of +9.