3331986 - Proposed quantity in MIGO for stock transfer scheduling agreement

There is a stock transfer scheduling agreement with a few schedule lines having dates in the past and in the future. 
When simulating the posting of a 'Goods Issue' and a 'Goods Receipt' in the 'Post Goods Movement' (MIGO) APP, the proposed Qty is different in each case. 

SAP S/4HANA Cloud Public Edition

EKEK-ABRDT, EKEK, EKEH, ME_READ_LAST_RELEASE, LEINRF2K, XEBEFU_AUFBAUEN, ME_EKPO_READ_WITH_EBELN, ME_READ_ITEM_GOODS_RECEIPT, GOITEM-ERFMG, MIGO, Goods Issue, Goods Receipt, stock transfer, scheduling agreement, schedule line, proposed quantity, date , KBA , MM-IM-GR-MIGO-2CL , Goods Receipt from External Procurement (MIGO) (Public Cld) , Problem