How to prevent line splitting in sales orders if there are on hand?

How to prevent line splitting in sales orders if there are any on hand?, sales orders have the flag allow partial shipment of lines set to "Y" activated because if there is not enough on hand it is desired that the split be done, we see that the two lines make the reservation but sets two different dates for the scheduled arrival and ship date.

We attach screenshoots and GOP set up.

Thanks