Absolutely, where trade agreements provide coverage for goods or services, there are thresholds that are indicative above which those trade agreements apply. When you apply a set-aside, the set-aside provides an exemption. It sets that procurement aside in whole or in part from the applicability of the trade agreement.
For any actions undertaken under the threshold, the trade agreements do not apply. For any actions taken above, you have to look at whether or not it should be set aside, in this case, for aboriginal businesses.