Show Linked entries on Data Table

I'm working on the data table of an Insurance Installment Plan.

Case 1:

  • Below is the initial schedule that has 10 entries.
  • The business senario is sometimes if an installment is overdue, clients will ask whether they can pay a half amount of that installment (in this case ID#2) first and pay the remaining amount a week later or so.
  • In this case admin will create a new installment that is linked to ID #2 (total amount of both will be equal to the initial amount of installment ID #2). After being added, that new installment will be displayed right under ID#2

Initial payment plans

Case 2:

  • Sometimes clients want to pay several installments in advance (eg: 3, 4, 5 & 6).
  • Instead of manually adjusting the Scheduled Payment Amount of all those entries, admin will click Transfer Installment Amount button to evoke this popup. Then select source amount from the Installment Range area (From ID# 4-6) and the target in Target Installment (ID #3).
  • After the amount is transfered, the Installment Schedule table will be displayed like this

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My questions are:

  • (For case 1) ID of new created installment should be 11 or 2.1? And why?
  • (For case 2) Any new approach or adjustment to make the current app flow of transfering amount more intuitive?
  • (For both case 1 & 2) Any way to get rid of link icons & also the column Linked to ID & add something different but can cover that business needs?