Yeah it was trev, he said he has an electrical engineer working on a prototype and wondered whether EV power would sell me a BMS without buying the batteries from them. I am hoping I could just get the components from EV power and solder up the 24 units myself to save the labour time/cost but I haven't followed that up yet.
The batteries will still cost close to 5 grand once the BMS and charger are paid for, but I think it will be worth it. Performance estimates
look good too.