Want to understand the Impact of F43090.LTQP on receipt routing

Dear Support,

I m having some difficulty to understand the design/ purpose of leadtime quantity percentage field LTQP in supplier item relationship.

1. What is all purpose of F43090.LTQP ?

2. Why DD item- LTQP is set to default 90% ?

3. What will be the impact of LTQP on receipt routing by having other than 90% value in this field? what would happen if i make it 50% ?

4. For intercompany orders, how to show a warning message at ship confirmation if the supplier item relationship not found in F43090 for receiving branch? or any workaround?

5.I do see, while moving inter company purchase order form TRAN to STK  using row exit to move shown rows, it moves only first line to STK not all lines (when LTQP is blank)- i know  this is the bug but when I have 2 lines, 1st have blank LTQP and 2nd line has 90% LTQP then it moves 1st line to STK but don't move 2nd line to STK(even though it had 90% LTQP) and by defining vice versa LTQP both lines got moved to STK - Why?