_Originally posted by @S3RK in https://github.com/bitcoin/bitcoin/pull/24984#pullrequestreview-952900468_

> With current implementation we don't save the rescan progress and on the next load we will have to start from scratch. Is it possible to save the last processed blocked at shutdown?

It would be nice if wallet code would call `WriteBestBlock` and save the last scan position if it is interrupted during a sync. This could be implemented by trying to save the scan position during the shutdown, or by just periodically saving the scan position after an interval, similar to indexing code which saves sync position once every 30 seconds:

https://github.com/bitcoin/bitcoin/blob/f0a834e2f10a0aa60c7cc76e9f3eb090168a32e5/src/index/base.cpp#L170-L175
* This can happen when restoring an old  backup that does not contain
             * the mostly recently created transactions from newer versions of the .
             */
            // l
            for (const CTxOut& txout: tx.vout) {
                for (const auto& spk_man : GetScriptPubKeyMans(txout.scriptPubKey)) {
                    for (auto &dest : spk_man->MarkUnusedAddresses(txout.scriptPubKey)) {
                        // I
                        if (!dest.internal.has_value()) {
                            dest.internal = IsInternalScriptPubKeyMan(spk_man);
                        }
                        // s
                        if (!dest.internal.has_value()) continue;
                        // I
                        // (
                        // a
                        if (!*dest.internal && !FindAddressBookEntry(dest.dest, /* ase)) {
                            SetAddressBook(dest.dest, "", "receive");
                        }
                    }
                }
            }
            // B
            // w
            TxState tx_state = std::visit([](auto&& s) -> TxState { return s; }, state);
            return AddToWaet(MakeTransactionRef(tx), tx_state, /*upptr, /*fFe, rescanning_old_block);
        }
    }
    return false;
}