the only official voice in the thread i linked to was sir no leaning towards fbtn in first battle + grapes = fbtn in second battle.
Yet in the other thread I just linked, Bryon himself said Grapes = new phase...
Bryon himself said it because the existing REG says so:
Playing a Negate All Hero on the second rescue attempt does not negate The Long Day on the first rescue attempt. The failed rescue attempt is resolved, so the second rescue attempt is not effected by the first rescue attempt (e.g., play by the numbers). The second rescue attempt is treated as a second Battle Phase, not an additional battle.
If you start a new battle, you start a new battle phase.
I saw that it could go either way, as Sir Nobody did. But I just figured I should go with what the existing REG says. The exsiting REG ruling has its benefits: less ongoing abilities to clutter up the second battle, and fewer abilities in second battle trying to reach back into the first battle. If they are in separate phases, things stay a lot cleaner.