The total transaction count (for progress estimation) is counted as the known count at the last checkpoint, plus an estimated number per day.

The last checkpoint is now 996 days ago, and its estimated 60000 transactions per day leads to a total estimate of 96M transactions, while the real number is around 183M.

Fix this by updating the count, timestamp, and rate of transactions... with or without adding a new checkpoint.
{
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 2)
        throw runtime_error(
            "waitforblock <blockhash> (timeout)\n"
            "\nWaits for a specific new block and returns useful info about it.\n"
            "\nReturns the current block on timeout or exit.\n"
            "\nArguments:\n"
            "1. blockhash to wait for (string)\n"
            "2. timeout (int, optional, default=0) Time in milliseconds to wait for a response. 0 indicates no timeout.\n"
            "\nResult:\n"
            "{                           (json object)\n"
            "  \"hash\" : {       (string) The blockhash\n"
            "  \"height\" : {     (int) Block height\n"
            "}\n"
            "\nExamples:\n"
            + HelpExampleCli("waitforblock", "\"0000000000079f8ef3d2c688c244eb7a4570b24c9ed7b4a8c619eb02596f8862\", 1000")
            + HelpExampleRpc("waitforblock", "\"0000000000079f8ef3d2c688c244eb7a4570b24c9ed7b4a8c619eb02596f8862\", 1000")
        );
    int timeout = 0;
    uint256 hash = uint256S(request.params[0].get_str());
    if (request.params.size() > 1)
        timeout = request.params[1].get_int();
    CUpdatedBlock block;
    {
        std::unique_lock<std::mutex> lock(cs_blockchange);
        if(timeout)
            cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&hash]{return latestblock.hash == hash || !IsRPCRunning();});
        else
            cond_blockchange.wait(lock, [&hash]{return latestblock.hash == hash || !IsRPCRunning(); });
        block = latestblock;