Physical Inventory Initial Load - Do you take MC.1 or MMBE balance?

We are moving over all the materials from one plant to another.

The existing Plant 1234 in SAP is being moved to new plant 5678 under new Co Code and new Controlling Area.

We wanted to load the Physical Inventory to new plant  5678 by downloading from existing Plant 1234.

The Stock count is different when we run TCODE MMBE and MC.1.  I understand we should be considering MMBE count to know the correct stock balance.

Any reason as to why do we see difference of stock count between MMBE & MC.1?

If we look up in Plant Stock view of the material it matches with MMBE, however MC.1 count matches with what is shown on Acctg View1 of the material master.

Thanks in advance for yoru valuable advise.