How can all delivery lines be split and manually grouped to a customer having 2 different sales order.Need to group all split deliveries in a single delivery id belonging to 2 different sales order of same customer.
For split line, select from action split then split the quantities according to your need.
For delivery all split lines to same customer, select all lines you need to make a one delivery & press the Ctrl button for each line then pick & ship these lines.