Understanding Promotional Scheme / Pricing Rule for Mixed Condition Free Products

Use case - model the following use case using either Promotional Scheme or Pricing Rules:

  • Buy X units of item A or B, get Y units of item F FREE
  • X units is reached by adding the orders for A and B in the same Sales Order
  • Tiers exists, for example:
  1. Buy 1 to 5 units of A or B (combined), get 1 to 5 units of F (basically buy 1 get 1)
  2. Buy 6 to 10 units of A or B (combined), get 12 to 20 units of F (buy 2 get 2 effectively)

Current attempted solution is to used mixed conditions and product discount slabs, such as in screenshots below:


The expected results are:

  • if order is 2 units of A, 2 units of B, then total 4 units would mean free 4 units of F
  • if order is 3 units of A, 3 units of B, then total 6 units would mean free 12 units of F

However, the actual results are:

  • if order is 2 units of A, 2 units of B, then total 4 units would only get 2 units of F
  • if order is 3 units of A, 3 units of B, then total 6 units would only get 6 units of F

It appears the pricing rule only calculates the freebies based on the more recently encoded line item. For instance, if user enters item A first, then item B later, then the calculation for free items only uses the quantity of item B instead of the total sum quantity of A and B.

Am I understanding this correctly or am I missing something?