On 09/05, I brewed a Rochefort 8 - mashed at 149F, with an OG 1.087, aerated with O2, pitched with a 3L starter of WLP540 Abbey IV, and fermented at 71-72F. Beersmith estimated this to land somewhere near 1.010.
Exactly a month later, it is at 1.023 despite rousing the yeast, bumping to 74F, and adding leftover yeast from the 3L starter.
Beersmith calculates 1.087 > 1.023 as 71.9% apparent attenuation. White labs states 74-82% attenuation.
At this point, it is a bit too sweet, and I don't know what else to do to bring it down.
Should I perhaps bring it up a few more degrees and rouse the yeast again? If yes, how high should I go at this point? Ambient house temperature is approximately 78 F.