The Beatles influence has been there since SLDD, at least from my point of view.
Scott has adopted the Bowie - like voice since 2007.. and slowly, he have adopted it more and more. That low vibrato style of singing very well known of Bowie, is what we can hear now in any SW show. Also, as a singer, i can tell you that singing like this is one of the easiest ways of singing. Scott with a baritone voice, can really mold his voice to this style and he has used it for those high notes that live, are really hard to hit. Ex: Do it for the kids - the bridge of the song.
I LOVE David Bowie and i love Scott. They are main influences on my singing style and definetely, i admire them separately because even though Scott sings like Bowie now, he still have his own voice personality and well, Bowie will always be Bowie.
Now, the influence of Bowie in Scott can be notices in the writing of the lyrics since Tiny music.
I recall an interview where Scott himself said that he felt free of writing the lyrics of the songs without a pressure of making sense.. just fill the emotions with the words that came to this head even if it didnt make sense at all.
Without Sir David Bowie, Scott wouldnt be half as good as he is. But, you know, thats like, uhm, my opinion man.