Bittorrentでダウンロードしたファイルのハッシュ値が一致しなくて困る

Raspbianの新しいバージョンがリリースされていた(2018-06-27)ので，Bittorentファイルを入手してTransmission-gtkでダウンロードしました．

Download Raspbian for Raspberry Pi

http://downloads.raspberrypi.org/raspbian/release_notes.txt

2018-06-27:
* New first-boot configuration wizard added
* Recommended Software installer added
* Bluej, Greenfoot, NodeRED, Claws Mail, VNC Viewer removed from image - can now be installed from Recommended Applications
* Qpdfview PDF viewer installed instead of Xpdf
* Version 65.0 of Chromium browser included, with latest Flash player
* Volume up / down keys now change by 5% increments and affect currently-selected output device rather than internal device only
* Network plugin now remembers previously-entered WiFi network passwords when prompting for reconnection
* Serial port and serial console can now be switched separately in Raspberry Pi Configuration
* Lxkeymap keyboard language setting application removed - replaced with dialog within Raspberry Pi Configuration
* Wifi country and keyboard language setting dialogs in Raspberry Pi Configuration now callable from other applications
* New version of Piboto font included to render with correct weight under some rogue applications
* Reconnection to Bluetooth audio devices on reboot improved
* Disable click-to-rename behaviour in file manager if single-click selection enabled
* Appearance Settings dialog makes config changes to some Qt files to match selected theme
* MIME file type associations improved
* Multiple desktop management options removed from mouse middle-click menu
* Menu shortcuts to Raspberry Pi website amended
* Python 2 IDLE menu link removed
* Sample Magpi PDF installed in /home/pi/MagPi
* Various minor tweaks, bug fixes and appearance changes
* Bluetooth updates
- Firmware with Bluetooth 4.2 features
- SCO profile suppot added via bthelper.service
* Linux kernel 4.14.50+
* Raspberry Pi firmware 748fb17992426bb29d99224b93cb962fefbdc833

一晩経って確認するとダウンロードが終わっていたので念の為ハッシュ値を確認すると合いません．

$ ls -l ./2018-06-27-raspbian-stretch-lite.zip
-rw-r--r-- 1 mk mk 366870528 6月 30 03:02 ./2018-06-27-raspbian-stretch-lite.zip
$ sha256sum 2018-06-27-raspbian-stretch-lite.zip
ce2d2babed81d5b2d6b919dc8dc92bc915a7d89f09f3aaad1d9ae01f2471eb25 2018-06-27-raspbian-stretch-lite.zip
$ echo 3271b244734286d99aeba8fa043b6634cad488d211583814a2018fc14fdca313
3271b244734286d99aeba8fa043b6634cad488d211583814a2018fc14fdca313

Transmission-gtk の該当Torrentで右クリックし，「ローカルデータを検証」を行うとダウンロードファイルが99%になりました．この状態でしばらく放置すると再度100%になり，今度はハッシュ値が合致しました．なぜこういう動きになったのかは謎です……．

環境

$ dpkg-query -W transmission-gtk
transmission-gtk 2.94-1+b1
$ dpkg-query -W transmission-common
transmission-common 2.94-1
$ lsb_release -d
Description: Debian GNU/Linux unstable (sid)
$ uname -m
x86_64