Currently rebuilding in one of my leagues. Best advice on how I should go about it? And how long I should aim for it to take?

Yup, what Garden said. Very team and league dependent. But sell off RBs and any aging players that are still relevant. Come in season time, keep a roster spot open for rookies who flash on the waiver wire

Along with what they said above, target rosters that have older players and trade for their firsts 2-3 years out if your league lets you. Another thing is don’t be afraid to “lose” a trade if it helps you so what you’re trying to accomplish

like said above, dependent on current roster and your current capital. I think 2-3 years is reasonable. I tore a team down towards end of 2020 and won a ship on 2023. overall capitalize on sell and buy windows. don't buy super high or sell low

It’s an 8 team league and I figured I’m not really going to be contending this year so I started pushing for some draft capital and traded off a lot of my older guys