His bankai powers are essentially to apply either his Quincy abilities, Hollow powers, or both. The core ability of Ichigo’s zanpakuto is to harness his Hollow and Quincy powers.
That’s why we see Blood Chains Ichigo as the Hollow version of his bankai. Most likely he also has a Quincy version of his bankai. The manga hints that he possesses a hybrid ability of his Quincy and Hollow abilities, which explains why he merges both blades.
Rather than being a completely new bankai, Blood Chains Ichigo is just a bankai technique, similar to how some Shinigami have different stages or forms of their Bankai, like Byakuya or Yamamoto.
@ripalek My guess is yes to all of them. Basically, the core ability of Ichigo’s zanpakuto is possibilities and defying fate (within the racial framework of the Three Worlds)