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 (!wtxIn.hashUnset())
        {
            if (mapBlockIndex.count(wtxIn.hashBlock))
            {
                int64_t latestNow = wtx.nTimeReceived;
                int64_t latestEntry = 0;
                {
                    
                    int64_t latestTolerated = latestNow + 300;
                    const TxItems & txOrdered = wtxOrdered;
                    for (TxItems::const_reverse_iterator it = txOrdered.rbegin(); it != txOrdered.rend(); ++it)
                    {
                        CWalletTx *const pwtx = (*it).second.first;
                        if (pwtx == &wtx)
                            continue;
                        CAccountingEntry *const pacentry = (*it).second.second;
                        int64_t nSmartTime;
                        if (pwtx)
                        {
                            nSmartTime = pwtx->nTimeSmart;
                            if (!nSmartTime)
                                nSmartTime = pwtx->nTimeReceived;
                        }
                        else
                            nSmartTime = pacentry->nTime;
                        if (nSmartTime <= latestTolerated)
                        {
                            latestEntry = nSmartTime;
                            if (nSmartTime > latestNow)
                                latestNow = nSmartTime;