The original campaign was not a recall. That was a TSB for folks who were having vibration issues. Some time after that NHTSA/DOT had Hankook issue a recall due to sidewall failures. If it was my car, I would have had them changed immediately once the sidewall failure issue became known.
When the original TSB was announced, and there was no known safety issue, it made perfect sense to keep the Hankooks on the car as long as you had decent tread. Once the safety issue became known, this became a full recall. No time limit, but it's risky to have these on the car. You really wouldn't want a tire to fail on the highway.
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What Conti tire were you offered?
Since this is a recall, you may want to try contacting Hankook directly. They may have another dealer who can assist with a credit toward whatever tire you want. There will obviously be a dollar limit, but any upgrade should be reasonable.
More info here:
http://www.hankooktire.com/us/tire-recalls.41.html