With regard to your multiple requests and due to the overload of the Bitcoin network, we managed to push the transactions, which have been stuck in the memory pool for a long time. This has been done using the RBF (Replace By Fee) feature. This method allows replacing a transaction in the memory pool by the same one but with a higher fee. It is worth mentioning that such Bitcoin transactions may be displayed as double-spent in the block explorers but it doesn’t relate to anything illegal.
Apart from this, we have significantly improved the algorithm of transactions’ creation. And, given the fact that we have implemented the SegWit support back in August, the Bitcoin transactions of our users have now a higher priority in the memory pool, compared to the transactions created without SegWit.
These updates will prevent BTC transactions of our users from getting stuck in the memory pool.
We will continue improving our services and join all efforts to provide the best experience for you.
Your CEX.IO Team