Bluesmart IP65 + AGM60L-DIN - recommended charging mode

I have a Blue Smart IP65 12V/10A charger. I use it to charge an AGM60L-DIN (12V) 60Ah/640A battery, and I’m currently using the factory-set ‘Normal’ mode. I’ve recently come across the suggestion that the ‘High’ mode is actually the correct one. Could you please advise which setting is appropriate for my battery?