SAP WM Initial Stock upload with Storage unit

Dear Team,

Please advice the initial stock upload for SAP WM with storage unit(Mixed storage)

I m planning to have MB1C - LSMW with 561 movement type

Then another LSMW for LT01 where material & qty will be entered in initial screen and

in second screen for Source quant will be entered the 998 quant no with storage unit blank

and Destination bin no with required storage unit.

Expecting the storage unit to get created(LEIN table) if doesn't exist in system and update in LQUA table.

If already Storage unit is update for another material in another line item of upload data then system should update the stock with the storage unit.

I have gone through multiple post with Initial upload but couldn't find  detail about Storage unit cases.

Thanks in advance.

Regards

Max