Looks compelling at the first glance. But a careful look at the boat from bow to the Sail doesn't look like a delta.
Second in none of the underway pictures the aft planes are out of the water. That's just wrong for a submarine. Those things are almost never out of the water when the boat is out at sea.
Third, at the bow of the image in the tweet. You can easily make out 2 hatches. Whereas in the press release for the launch of the boat. You only see one hatch.
The submarine "Moscow Region" transferred to the fleet after modernization
Fourthly, the former missiles farm, when removed, still has a gentle slope when moving from sail to the aft of the boat. Whereas, in the picture attached to tweet, it's at the same level as the section fwd of the bow.
That's the reason why, I don't think that we are looking at a modified Delta in the tweet.