Did they manage to find similar roles in government or industries, did they downshift in their occupations or did that part of the old culture just completely die out?
Are there any remnants of the culture of the old upper and educated industrial/government etc classes in the cultural genome of modern Russia, other than purposefully copied aspects of culture, or is this cultural genome mostly or completely dominated by the new upper class culture (mostly government / party members I guess?) that was brought on by the Soviet rule and later its collapse?
And just to clarify I don’t mean biological genome, I believe talent, capability to succeed and maintain a high social status are prevalent through all social classes. So I’d assume eventually a similar upper class would form in the place of the old, but the question is, how much continuity is there between pre and post soviet upper class culture in Russia?
And upper class here means most of the well off classes that were persecuted and killed by the soviets.
There was very little, if any, crossover between the upper-class culture before and after the revolution.
As I'm sure you'll know already the vast majority of the former royal family and nobility were either killed or fled of their own accord after having their belongings seized by the government. Those who stayed had to hide their identities or risk being killed in purges, and so wouldn't have wanted to make themselves prominent as members of the upper class again. Douglas Smiths' Former People will give you a much more in-depth description of life for those who stayed behind than I could possibly hope to, so I recommend that that be your next port of call.
Some of the former nobility tried to 'get in,' as it were, with the new government; maybe the most notable example being Grand Duke Kirill Vladimirovich. On the 14th of March 1917, he donned a red armband and went to swear fealty to the provisional government before having a red flag raised above his palace. This did nothing to ingratiate him with the Bolsheviks, however, and when they took over Kirill fled too.
Another interesting example is Vladimir Nabokov's family. His father (also called Vladimir) had been one of the most progressive members of the Duma prior to the revolution; he considered himself a centrist but personally, I think he was more akin to a modern liberal at least. He had always been in favour of western-style democracy in Russia and naturally got very involved with organising the provisional government—but this made him an enemy of the Bolsheviks, so of course he and his family had to leave in 1919.
This account of a post-Revolution visit to the Alexander Palace might be of interest to you. The tour guide criticises every aspect of the former imperial family's comparatively bourgeois taste:
"You will see in how very bad taste are the rooms. It was all in that style, what they had. All in very bad taste. Even the pictures, they are bad."
"The bedroom of the Tsar. The taste is very bad - the lamp-shade that terrible colour..."
A lot of former palaces were done up after the revolution to be more generic and in line with that eternally popular neoclassical style, which I suppose is what this guide would have considered to be in good taste. Styles of dress and decor which had been popular during the Belle Époque (e.g the Empress' beloved art nouveau) were hated during the Soviet era as symbols of the old order.
The hallmarks of upper-class culture prior to the revolution—country houses, balls and parties, holidays in the Crimea—remained afterwards in a sort of skeletal way. That is, in things like dachas and sending your children to Artek for the summer. These were aspirational things that the majority of Soviet citizens couldn't afford. But these weren't concepts being kept alive by the old upper classes, they were there in place of those old markers of success.
In summary, I would say that there was nearly no continuity between the Russian upper-classes prior to and after the revolution in terms of people or culture. Even simple things that had been popular for centuries among the upper and middle classes—samovars, for example—experienced a huge decline in popularity after the revolution. So too did everything else.