The code above do the following:
1) Release event for packet indication.
2) Set adapter into passthru mode (the state it was before you set TUNNEL mode).
3) Flush packet queue associated with the adapter.
For temporary stop filtering: 1 – is not necessary, 2 – should be be done, otherwise (if you exited the loop) the network will be forzen after all WinpkFilter internal buffers are used, 3 – should be done because if you have existed packet reading loop, to that moment you can have internal buffer pool exosted and the network frozen.
So, in addition to exiting the loop you should set the default mode over the interface and flush its packet queue. If you want to restore filtering, then set tunnel mode and enter the loop again.