if (IsProtocolV2(nHeight) && nVersion < 7)
        return DoS(100, error("AcceptBlock() : reject too old nVersion = %d", nVersion));
    else if (!IsProtocolV2(nHeight) && nVersion > 6)
        return DoS(100, error("AcceptBlock() : reject too new nVersion = %d", nVersion));

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inline bool IsProtocolV1RetargetingFixed(int nHeight) { return TestNet() || nHeight > 62016; }
inline bool IsProtocolV2(int nHeight) { return TestNet() || nHeight > 62016; }
inline bool IsProtocolV3(int64_t nTime) { return TestNet() || nTime > 1467633600; }