The SQF practitioner shall:
i. Be employed by the distribution or storage site as a company employee on a full-time basis;
ii. Hold a position of responsibility in relation to the management of the distribution or storage site SQF System;
iii. Have completed a HACCP training course;
iv. Be competent to implement and maintain HACCP based food safety plans; and
v. Have an understanding of the SQF Food Safety Code and the requirements to implement and maintain SQF System relevant to the distribution or storage site scope of certification.
As pooled pointed out, in the SQF code it does state that a Practitioner must have completed a HACCP training course. I would interpret that as any "backup" Practitioners would need to meet the same requirements.
For instance, at our facility we have 2 "Lead Auditor backups," and both employees meet the above conditions (we are essentially the backups for our SQF Practitioner).
I'd recommend you ask your employer if you can take an online or in-person HACCP course and be reimbursed by the company for your expenses, as they placed you in a position that requires the training.
"Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution."- Albert Einstein