deleting char with soulbound precursor
The precursor will stay in the bank but it will be useless – no other character will be able to withdraw it (and if I remember correctly you can’t put things in the Mystic Forge from the bank.)
Making a new character with the same name won’t help – the game will still consider them two separate characters and won’t let you pick up the precursor.
You’ll need to finish the legendary before deleting the character.
“Life’s a journey, not a destination.”
What’s the rush to delete the character with the soul-bound precursor? Maybe we can help you address that issue (depending on what it is).
Your other option would be to write a ticket to support and ask them if they could please rebind it to another of your characters, so that you don’t lose the ability to build on it.
I don’t know if they would, but it’s certainly an option to pursue.