Note that it's the p80 (80% of cases get decided within this time). For the Chicago office it currently says 10mo but our interviews are scheduled for < 4 months since submission. and IIRC that estimator showed a way higher number back in March (maybe 14 months?), then our individual estimates on our dashboard also swung wildly (at some point it showed 16+ months, then it dropped to 9 months).
So... if your husband's case is not that complicated, you can probably beat the estimate. For peace of mind I just have a calendar reminder to check the status weekly (so we don't miss anything) and otherwise try to not think about it.
Oh, and you can see copies of everything they send you in the document tab of your USCIS dashboard, in case they lose it in the mail. Still waiting for our interview notices after 12 days