on 13 DEC 2016 he found a transfer of 49.5. btc was sent from his account to
If he didn't initiate any send action there, I don't see how it could be a glitch in Mycelium.
Unfortunately, from what I read, my conclusion is that somebody else got access to the private key of 13uzBESjqTT87ak4uAipKUoP8EuVHcQk2e and stole the coins by sending them to 1EF3DDBaPzbpJ5cXHVW2gZkyG1Jd4FotFW.
On the other hand, I see multiple send actions from 13uzBESjqTT87ak4uAipKUoP8EuVHcQk2e to 1EF3DDBaPzbpJ5cXHVW2gZkyG1Jd4FotFW,
even with change back to 13uzBESjqTT87ak4uAipKUoP8EuVHcQk2e, hence I think that something is missing from the story.
He told me that he may attempt to send bitcoin the day before or the same day but not sending the full 50 BTC
The owner isn't someone familiar with bitcoin / I asked him about the last two transactions to 1EF3DDBaPzbpJ5cXHVW2gZkyG1Jd4FotFW with low amount and he told me that the transfer was initiated by him .