I've quit sugar for months at a time and found that 2-4 weeks was the most difficult spot for cravings, after which it eased off (though never went away).
I don't have experience with alcohol, though, and I hear it's higher on a scale of risks for physical dependencies than a lot of substances, so sugar may be a poor comparable.
For me (regular drinker feeling it was getting a little too regular) it took a couple of months dry to stop wanting a drink most days, then about another 7 months until I didn't miss it at all.
I'm only 14 months in though, and I don't assume I'm finished. YMMV obv.
For me, the urges for sugar and alcohol are very very similar. I've never had urges to binge either, but cutting either out completely after semi-consistent use does result in similar cravings. And I've noticed that my urge for both seems to be reduced if I choose to eat large meals at night instead.
I've quit sugar for months at a time and found that 2-4 weeks was the most difficult spot for cravings, after which it eased off (though never went away).
I don't have experience with alcohol, though, and I hear it's higher on a scale of risks for physical dependencies than a lot of substances, so sugar may be a poor comparable.