How to create rules for putaway tasks to ensure putaway qty is in mutiples of FLM

Hello

We have need   to fulfill two locators (Picking and Reserve )  and  split   Quantity   in Multiple of FLM ( fixed lot multiplier)

For Example  Total Trxn Qty = 100 and FLM = 10

Picking locator available  space = 45

Reserve locator  available space =  55

With current rules ,  I am able to generate two tasks with 45 and  55  but business want to  ensure that  Tasks are created  in multiples of  FLM (10)

so two  tasks  should   be created  with qty

for Pickface = 40

for  reserve = 60

Please help .