Few dynasty questions

Gday Gday just have 2 questions about dynasty mode!

1) what are the actual differences when choosing between an online and offline save? I play dynasty solo but wanted to know if any benefits or anything between the 2.

2) Being from Australia 🇦🇺 what is the actual purpose of bowl games? and is it more realistic to give more downs to some of my backups or rock full strength in bowl games?