Thank you very much G. Michael for your comment. It is very much appreciated to know that others are interested in my research.
The former rooms of Nicholas I have been restored in the last two years including the corridor #398 - 400. There is no access to the private Majesties Own Staircase.
Since they are now restoring the Small Church on the 2nd floor, the Small Church Staircase may be closed. Another way is by the Saltykov Staircase or, after touring the former Ladies-in-Waiting rooms on the 3rd floor, walking down the corridor #359. It all depends on what rooms are closed at the time for continued renovation or changing of exhibitions.
Joanna