The instructor certificates, taught by a Part 61 school that employs CFIs full-time.
Becoming a CFI is the most efficient way to build hours toward an airline career and the most direct way into the TPP pipeline. We hire from our own training pipeline first.
FAA references that govern Certified Flight Instructor (CFI / CFII):
Email gets answered, usually same day. A discovery flight is the most direct way to find out if this is the right program.