Residential building permits in Pennsylvania are governed by local ordinances, and the timeframe and extension requirements are set by the municipality issuing the permit. I'd suggest you call the administrative office in your township and speak with someone who can give you the answers you're looking for.
According to the township website, the North Versailles Township Administrative Offices are open Mon-Fri. 9:00am- 4:30pm. You can reach the office by calling 412-823-6602.
Of course, as with all of my online answers, my advice is limited by the brevity of your question and the facts provided. Additional information would be required to provide definitive legal advice, so this answer isn't intended to, and does not, create an attorney-client relationship.
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