PM numbers - custom number auto generate for different PM types

Associate a specific new PM number sequence with a specific PM type. In certain situations we deal with a whole organ which is stored in one of the referral fridges. This is for a whole organ only (e.g., brain) without the deceased (i.e., the body is retained at a different mortuary and the whole organ is transferred to the our mortuary and stored in a referral fridge). Post mortems for these organs are normally registered in the Paeds/Peri dashboard in Eden but they have their own Post Mortem number format. The next PM number must usually be given in this series so that when a new 'Post Mortem Type' of "Referral - Whole Organ" is selected, the next PM number in the series is given. Currently as a workaround, the next PM Number is identified based on the highest number used previously and this is entered into the PM number before the PM type is selected. Additionally, this item must appear in the PM reports for Paeds/Peri.