Has there ever been a succesful non-finalist?

[Maxxie.]

To anyone’s knowledge has their ever been acts who didn’t make the final but go on to bigger things, maybe even several years later?

[Morgan.]

Ed Drewett (2014) has written singles for Oine Direction, Little Mix, Louisa Johnson and Jonas Blue
AJ and Chloe (2013) are/have been Strictly Pro's
Charlie Wernham (2008) is now an actor and has been in things like Bad Education and Hollyoaks

All semifinalists.

[GiRTh]

The cellist at the Royal Wedding was on BGT with his whole family
Sheku Kanneh Mason (https://en.wikipedia.org/wiki/Sheku_Kanneh-Mason)
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