Here is a proposed release schedule for 0.19.0, the next major release of Bitcoin Core. Like for previous major releases I've aimed for a release 6 months after the last ( #14438).

2019-09-01 :heavy_check_mark: 
---------------
- Open Transifex translations for 0.19
- Soft translation string freeze (no large or unnecessary string changes until release)
- Finalize and close translations for 0.17

2019-09-15 :heavy_check_mark: 
---------------
- Feature freeze (bug fixes only until release)
- Translation string freeze (no more source language changes until release)

2019-10-01 :heavy_check_mark: 
---------------
- Split off `0.19` branch from `master`
- Start RC cycle, tag and release `0.19.0rc1`
- Start merging for 0.20 on master branch

2019-11-03 :heavy_check_mark:
---------------
- Release 0.19.0 final (aim)

If any specific dates or timeframes are a problem for you, let me know.

**Edit:** schedule was moved two months back on 2019-05-07, for reference, the old schedule was:
```
2019-11-01    Soft translation string freeze
2019-11-15    Feature freeze
2019-12-01    Split off 0.19 branch from master
2020-01-03    Release 0.19.0 final (aim)
```
{
    const CTransaction& tx = *ptx;
    {
        AssertLockHeld(cs_wallet);
        if (!block_hash.IsNull()) {
            for (const CTxIn& txin : tx.vin) {
                std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range = mapTxSpends.equal_range(txin.prevout);
                while (range.first != range.second) {
                    if (range.first->second != tx.GetHash()) {
                        WalletLogPrintf("Transaction %s (in block %s) conflicts with wallet transaction %s (both spend %s:%i)\n", tx.GetHash().ToString(), block_hash.ToString(), range.first->second.ToString(), range.first->first.hash.ToString(), range.first->first.n);
                        MarkConflicted(block_hash, range.first->second);
                    }
                    range.first++;
                }
            }
        }
        bool fExisted = mapWallet.count(tx.GetHash()) != 0;
        if (fExisted && !fUpdate) return false;
        if (fExisted || IsMine(tx) || IsFromMe(tx))
        {
            /* Check if any keys in the wallet keypool that were supposed to be unused
             * have appeared in a new transaction. If so, remove those keys from the keypool.
             * This can happen when restoring an old wallet backup that does not contain
             * the mostly recently created transactions from newer versions of the wallet.
             */