RAF Hampdens: question on paint scheme

Hi,

At this URL...

http://homepages.paradise.net.nz/southfly/hampden.htm

I have posted several pictures of 489 NZ Sqn Hampdens. I am trying to
gather information on why one Hampden (XA-Y) appears to be painted in
an 'ocean' grey and sky scheme, yet images of both earlier and later
Hampdens from the sqn show them in Green/Brown/Black schemes. (Of
course, the photo dates could be wrong...).

Can anyone shed any light on this matter, please? Was it a trial
scheme, as I have only ever seen this Hampden wearing it?

I am gathering info on the aircraft flown by 489 Sqn with the aim of
publishing a book on the topic... any data anyone can provide is most
welcome, esp. with regard to the Beauforts and Blenheims initially
operated by the sqn.

I managed to view several photos of the Mosquitos the sqn operated at
the end on WWII, so hope to publish some profiles soon.

Thanks very much,
Ian