Acetaldehyde question

I know the common causes of acetaldehyde. My beer is definitely finished after 12 days. The yeast had dropped and the beer is very clear. Sg 1.056 fg 1.014. A little higher than expected. Can a long lag and slow ferment cause acetaldehyde? That combined with opening the bucket lid quite a few times. Wondering if that introduced a higher amount of o2 than normal. I had checked the gravity a lot because it was a slow ferment and I was concerned. I made an identical batch before this that hit fg at day 3 and this one hit it at 8 days. Temp starts at 63 then ramps to 68. Then I bring up to 70-72 after I hit fg. Beer has a slight solventy taste up front then disappears and tastes pretty good. To me it seems more solvent like but it’s not strong. Just wondering if this is acetaldehyde.

Not sure I can answer your question directly. But I can say I have had a few beers lately which have started out with that heavy alcohol sensation to them, when there was no apparent reason for it.

In the end, both beers (one of which was around the gravity of yours) ended up losing the flavor after an extra week or so of cold storage.

Both ended up fairly clean - the higher gravity one took a little longer.

I don’t think regular gravity readings would have harmed the beer much, so I might expect the beer to right itself a bit in time with a cold crash (if not already done) and a little aging time.

Acetaldehyde is green apply flavor. Poor yeast health can cause Acetaldehyde and it should fade with aging. Acetaldehyde shouldn’t have a solvent flavor though. Per your ferm schedule it doesn’t appear high temps are to blame. Solventy off flavors can be caused by oxidation as well. Can you provide more info such as recipe and techniques?