On analysis of better photos and further consultation with a couple of other mossland regulars, it seems that 2-3 of the juvenile birds appear to be Stonechats! Confusion seems to have come from some of the birds appearing to show a hint of a pale supercilium and being perhaps a little paler in colour than usual. They are quite mobile and can be a bit distant at times, as well as frequently dropping out of view in the vegetation, so not always easy to get prolonged clear views.
So, it seems were back to 4 (possibly 5) Whinchat after all!
Little Woolden Moss LWTNR
This evening on the east pool
1 Greenshank, 1 Golden Plover and a handful of Lapwings.
1 Grasshopper warbler reeling by the west pools.