I have been looking at the discussion of the possible Alder Flycatcher in the U.K. I read that a few observers heard it call. Alder Flycatchers have a few different calls and not all are found on some of the CDs or tapes available.
I live in south Florida in the U.S. and get to see lots of Alder Flycatchers that show up about mid-August, to perhaps the first week of October. This seems to be the only place in Florida where we get a concentration of Alder Flycatchers for some strange reason. Anyway, I have recorded calls and songs of some of these birds, perhaps one of the calls is what was heard from the U.K. bird.
Here is a typical call: http://www.southfloridabirding.com/AudioFiles/alfl2.mp3
Here is another typical call: http://www.southfloridabirding.com/AudioFiles/alderfly.mp3
Here is a less typical call with the song, this may be the call that was heard on the U.K. bird, the call is first and then the song: http://www.southfloridabirding.com/AudioFiles/alderflyaugust28_08.mp3
Hopefully with all of the good birders present, someone will get a recording or video with a recording of the U.K. bird.
I have seen all of the discussion back and forth as to what it is, and everyone has a different opinion as to what it is. Photographs are always hard to I.D. a tough bird like a Willow or Alder Flycatcher. I would agree that it does not look like a Yellow-bellied Flycatcher, but again photographs can be deceiving.
Larry ManfrediHomestead, FloridaU.S.A.