From what I am seeing, the Exit 19 designation for I-79 NB on PA 576 WB may have to do with how it is planned to be signed EB at the Morganza Rd interchange.
Did anyone see any signage for the I-79 NB/Morganza Rd interchange installed yet?
EDIT (10-14-2021): I am planning to go 18 at I-79 and 19 at Morganza Rd unless I see evidence that I should do something different.