Appreciated if some guide can be provided.  
MRP lot size has been set to MB (Monthly lot size) 

It is known that with this setting, material are always bring in on the first working day of the month. 
Ex: Dep requirement 26-10-04 100 pcs 
Dep requirement 30-10-04 190 pcs 

When MRP completion, the PR item shown 1-10-2004 290 pcs, is that any possible to bring in material just right before dependant requirement 26-10-04 say about 24 or 25 of the month. 
Because. we dont tend to keep more stocks until actual requirement. 

Any comment are welcome. 

In that case you might like to consider lot size key WB (weekly). It will bring in material at the first working day of the week. In your case it is Oct 25, 2004

But in this case, I will have increase administrative cost on monitoring the material lot weekly. 
I want to have monthly lot size that group all the requirement, but bring in material as close as possible on the first requirement. 
Any comment are welcome.. 

How about manually change delivery date in PO item

Check your config. in OMI4 - scheduling may by ''1'" for Lot size of MB. 
Change to Blank. 

Friend PPS is correct, Schedule the "REQUIREMENTS DATE = DELIVERY DATE" option in Customizing for Lot Size MB (use Blank instead of 1) & your reqt 'll be met... 

We have similar problem and when I applied your solution, the proposed requirement date is perfect. 

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