Bahumat with Heal Sponge

Art357

Hello everyone,
I need some clarity in Heal Sponge node description..
So, I run suicides, kept my willpower active and went with this team 7* R2 HB & Hulk, 6* R4 Ultron & Nimrod, 6* R3 Omega Sentinel
And I took Professor-X path and went for Bahumat with Heal Sponge
In first try failed to beat using Omega Sentinel then went with Ultron and luckily his passive Heal block somehow helped me and I could bring Bahumat down to 40% into phase-3 and then my Ultron died then begun the nightmare
So, as of Heal Sponge node description, it says that Bahumat "EVERYTIME ATTACKER HEALS, BAHUMAT GAINS 1000% OF THE HEAL, BUT HE CANNOT RECOVER HIS HEALTH ABOVE THE CURRENT PHASE THRESHOLD"
It clearly says he won't regen above the current phase and after my Ultron died I went with Nimrod, HB, Hulk but he kept on regenerating again
He starts with Phase 3 and regenerates then gets back to 40%+ HP again and I push him to Phase-3 then Bahumat prompts as phase-3 then back to protection mode then again starts Healing again back to 40% HP above rinse and repeat the loop....
Now, my question is.. is the node description wrong or is it a bug ???

@Kabam Miike @Kabam Zibiit @Kabam Porthos @Kabam Vydious @Kabam Lyra or anyone who can answer !!!!!

I'm exploring 8.2 and this is the only path to make it 100% Exploration and then this issue