Sounds like more nonsense from NAPIT to me, night storage heater boards have been working fine for decades. Never done this in commercial / industrial 3 phase boards either. All MCBs are supposed to be rated for their max ampage in continuous use, so if there's an issue, they should be shaming/ naming shite MCB manufacturers.Only just starting to come in. Was at the last Napit event. Its to avoid circuits that are high use high current (ev) overheating theirs and neighbouring mcbs/rcbos. As ev chargers are high load over a long period.
Hence why Lewden now have a 39 way board