Surely Boeing are just acting on the recommendation from the Spanish CIAIAC. The final CIAIAC report contains following @rse-covering statement:
"It is recommended to The Boeing Company that a service information letter or similar document is sent to all the operators of Boeing 737 aircraft to make flight crews and maintenance personnel aware of the hazardous effects that a bird impact in the area of the NLG could have in the nose wheel steering system, and that precautionary measures should be taken in this case."