A company using the Just-in-Time (JIT) inventory methods likely would show the same net income under both absorption and variable costing because:

ending inventory would be valued in the same manner for both methods under JIT.
production is geared to sales under JIT and thus there would be no ending inventory and no fixed overhead costs deferred in inventory.
fixed overhead costs are charged to the period incurred rather than to the product produced under JIT.there is no distinction made under JIT between fixed and variable costs.