Yes two heaters in parallel with the second one on the other flat side of the nozzle block. Thats 96W total as each one is 48W.
I have a spare TH board set just in case, but its been running fine for months. Keep in mind because of PID its rarely at the full 24V, mainly at initial warm up, so the extra stress is minimal on wiring and circuitry. But as with any mod, this is not officially supported by Bambu, so do at your own risk.