Answer: modified rebuy
Step-by-step explanation:
Tetradic's situation can be defined as the modified rebuy. Modified Rebuy refers to a purchasing situation whereby an individual or organization buys goods that they've bought before but then changes the supplier or some elements in the previous order.
Based on the question given, Tetradic Solutions alters his purchase as the order was modified. In modified rebuy, the specifications of the product, prices, and suppliers can be changed as well.