Curate, connect, and discover
So Starscream is around 25 ish in human years in G1 and you take away the war he was definitely around 17 when he joined the war and lost Skyfire. Now when you're 17 you'll be in college/university and I think that's similar to the Cybertron thing in G1 the show.
Starscream goes on an exploration with Jetfire away from Cybertron and I'd like to think you have to be a certain age requirement and qualification to pass and G1 Starscream did go but in Skybound when Skyfire leaves Starscream doesn't go with him and he's seen as if following Skyfire's carer path. So he's definitely in his early teens and he didn't join the war in the beginning so he's been fighting for less than 200 years (which might be around 3 years in human terms except these guys age faster when they are younger)
So whilst G1 Starscream may be young Skybound is even younger and with my idea of Starscream and Ulchtar being a split personality with no memories of the other Starscream is mentally a 11 year old whose first action was killing and in total he would probably be around 12/15.
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