Did some rough measurements on the EO website. The length of said boat looks to roughly match that of the previous 093B SSNs.
There is also this timeline to consider, per the EO Sentinel website:
November 1: Drydock empty, previous (7th?) boat still inside the drydock.
November 6: Drydock empty, previous (7th?) boat still inside the drydock.
November 11: Drydock flooded, visibility poor due to clouds.
November 16: Visibility zero due to thick clouds.
November 21: Drydock flooded, no boat visible.
November 26: Drydock flooded, one boat visible. <--- We're here
Could this be the 8th (and final) boat of the 1st batch 093B SSNs? Or not?