Blockchain.info App transaction between ETH and BTC over 3 hours

[kpsuk]

Hi All,

Earlier today I made a transaction from ETH to BTC, after 3 hours it's still sitting at "In Progress - Sending Funds 1 of 3".
I read somewhere on here that you can overwrite that transaction by creating a new one, which Blockchain.info App has allowed me to do.
But!...
Now I have two transactions with  the same "In Progress - Sending Funds 1 of 3" with the seond for a slightly larger amount (because ETH has gone up since the first attempt).

Will the second transation overwrite the first?
Or will the first transaction still got through?
If so what will happen to the second transaction?

Keith