In mid-1917, before the Bolsheviks took power, there were some attempts made by Kerensky's provisional government to get the Romanovs out of Petrograd and onto a RN cruiser to Britain. Due to British dithering and problems with the Bolsheviks, this plan fizzled. However, suppose everything came together, and Kerensky got the deposed Tsar, as well as his wife and children, from Petrograd and out to Murmansk and on to Britain successfully? This is more of a details-based what if, but interesting nonetheless.