dear,
all alternative at SAP system can you handle by many method ,
1- if you didn't use this item again related to all BOM you can use
follow up material method .
you can use it at master data tap "mrp4" put discontinue indicator 1 also, put the follow up material.
after that go to specified BOM and link the follow up material item by follow up group,
2- if you will use two alternative item parallel you can use
alt.item method :
you make alt. item related to 2 item at one BOM , it will depend to strategy method
3- if you know the date that the old material will sufficient your production ,you can use the
changing note method
you will create changing note and after that apply it at the BOM .
thx.
Amira