That is correct (which I also didn't know until a year or 2 ago. Sundays are considered "Feast days", because technically it's 45 days from Ash Wednesday to Easter, so you have the 40 days of Lent plus 5 Sundays, which aren't included, thus the Lenten "rules" don't apply. Really? I never knew this. Still, i'm gonna try to hold out and not eat it on sundays, but it's good to know that if i get weak, i have a day i can give in on.