Hearings arise two ways, either initiated by the judge, or initiated by the requestor. The requestor won't ask for a hearing unless the judge signals the application is going to be rejected without more explanation. The judge won't ask for a hearing unless the application is somehow deficient on its face.
Based on the fact the warrant issued, the "story" in the application met the threshold for "shall issue" the ex parte order. See 50 USC 1805
https://www.law.cornell.edu/uscode/text/50/1805