For the last few days there have been complains that bitcoin transactions are taking hours and even days to complete and are unconfirmed.
This is due to backlog which is created due to unconfirmed transactions.
Currently there are around 37,000 unconfirmed transactions and their transfer rate is 8.2 per second. you can check the current status on blockchain website.
source: https://blockchain.info/unconfirmed-transactions
This situation is not only with bitcoin, other digital currencies are also affected. Litecoin has over 340 pending transactions and Ethereum has over 3000 pending transactions.
source: https://bchain.info/LTC/
source: https://etherscan.io/txspending
so our recommendations are to trade for Litecoins and Ethereum rather than bitcoin as bitcoin is not created for immediate transfers of mass volume.