If it was me I'd have it coming out the DT and under BB. Leave the BB BSA, simplest and cheapest. I'd rather have it inside the chain stay again but maybe is a faff for the builder
This is broadly where I'm at and I feel like I've enough research to begin talking to a builder about it.
@Netakure started
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If it was me I'd have it coming out the DT and under BB. Leave the BB BSA, simplest and cheapest. I'd rather have it inside the chain stay again but maybe is a faff for the builder