Am I required to follow UAB's normal call-in procedure when taking FMLA leave?

Yes. Under the regulations, an employee must comply with an employer’s call-in procedures unless unusual circumstances prevent the employee from doing so (in which case the employee must provide notice as soon as he or she can practicably do so). The regulations make clear that, if the employee fails to provide timely notice, he or she may have the FMLA leave request delayed or denied and may be subject to whatever discipline the employer’s rules provide.