"Its not a different timeline because he only travelled from it to the 30th century which was in normal continuity without travelling through dimensions. The bud could come away totally and become a distinct timeline but it was achored in a loop to continuity 30 century so this never happened"
Then you wer wrong when you said Superboy couldnt travel from his pocket universe.
For me its time manipulation. For you its not. Live with it 😉