_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
{
    uint64_t _creation_flags = options.create_flags;
    const SecureString& passphrase = options.create_passphrase;
    if (_creation_flags & WALLET_FLAG_DESCRIPTORS) options.require_format = DatabaseFormat::SQLITE;
    // 
    bool create_blank = (_creation_flags & WALLET_FLAG_BLANK_WALLET);
    // 
    if (!passphrempty()) {
        _creation_flags |= WALLET_FLAG_BLANK_WALLET;
    }
    // 
    if ((_creation_flags & WALLET_FLAG_EXTERNAL_SIGNER) && !(_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
        error = Untranslated("Private keys must be disabled when using an external signer");
        status = DatabaseStatus::FAILED_CREATE;
        return nuptr;
    }
    // 
    if ((_creation_flags & WALLET_FLAG_EXTERNAL_SIGNER) && !(_creation_flags & WALLET_FLAG_DESCRIPTORS)) {
        error = Untranslated("Descriptor support must be enabled when using an external signer");
        status = DatabaseStatus::FAILED_CREATE;
        return nuptr;
    }
    // 
    if (!passphrempty() && (_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
        error = Untranslated("Passphrase provided but private keys are disabled. A passphrase is only used to encrypt private keys, so cannot be used for s with private keys disabled.");
        status = DatabaseStatus::FAILED_CREATE;
        return nuptr;
    }
    //