At first the result was negative (when the results were interpreted 5 minutes after completing the test, as indicated in the instructions). However, a second test line (T) appeared after an hour - does this mean the test is actually positive?

At first the result was negative (when the results were interpreted 5 minutes after completing the test, as indicated in the instructions). However, a second test line (T) appeared after an hour - does this mean the test is actually positive?

No. In order for the results to be properly interpreted, you must read the results 5-10 minutes after completing the final step (Step 7) of the test. Any interpretation outside of the results reading window may lead to an incorrect result.