ND logic. The guys that played the entire season were just backups.
I can actually answer this because I met two of them, LOL.
The starting LT, Jagusah, was hurt in preseason. His backup was Baker, who then got beat out by Knapp in fall camp.
The Center, Craig, got hurt early in season, Coogan replaced him.
The LG was Pendleton, who got beat out early in season.
The RG, Schrauth, got hurt & replaced by Spindler.
Baker is out of eligibility and gone. Coogan, Spindler & Pendleton all entered the portal after the season because all the original starters are back, and they all have eligibility past this season. (Jagusah, Knapp, Craig, Schrauth, Wagoner).
I talked to him last night, and even though ND has a couple kids (Lambert & Absher) a lot of ND fans want to pass up starters, they look like they will line up the following way at the end up spring:
LT Knapp
LG Schrauth
C Craig
RG Jagusah
RT Wagoner
ND fans want Lambert to start and for Knapp to move inside. Typical spring freak outs. LOL