This is all just guess work.
Look at the values in the database that ACF uses. Options table, option_name = ‘acf_pro_license’
add an action as early as possible, I’m not sure how early you need to do this but it needs to be before ACF gets the value. Even then I don’t know if it will work because the option is auto loaded.
// this is the function to call in add_action()
function update_my_acf_license() {
update_option('acf_pro_license', 'value from DB', true);
}