Update May 22: Steve, VK6SJ now plans to be active as VK9XX from  Christmas Island (OC-002) [425DXN 1566] from 28 May  to  11 June.  Expected hours of operation are  11-15 UTC and 22-00 UTC on a daily basis.  "If I get ahead of  schedule  in my work",  he says,  "I may squeeze in a day off, in which I will see if I can tune up the dipole on  6, 10  and 15 metres during the day". He plans to operate a separate band each night,  but if there is  no propagation  "I will change band rather  than call into nothing":

         Date    Band    QRG FT8   QRG SSB
         ---------------------------------
         28 May   20m    14.090    14.280
         29 May   40m     7.056     7.180
         30 May   30m    10.131      -
         31 May   80m     3.567     3.625
         01 June  20m    14.090    14.280
         02 June  40m     7.056     7.180
         03 June  30m    10.131      -
         04 June  80m     3.567     3.625
         05 June  20m    14.090    14.280
         06 June  40m     7.056     7.180
         07 June  30m    10.131      -
         08 June  80m     3.567     3.625
         09 June  20m    14.090    14.280
         10 June  40m     7.056     7.180
         11 June  30m    10.131      -

All FT8 operation will be Fox & Hound mode. "I will stop FT8 at the end of each hour and try SSB for 10 minutes minimum. If I get a run  on SSB,  I'll stay there  until I don't,  then return to  FT8.  SSB operation will be split frequency, listening 5KHz up and  +/- QRM". 
During the CQ WW WPX CW Contest  "I may answer a bunch  of stations calling CQ test,  but I don't think my CW is up to managing a pile-up".

Update May 4: Operation rescheduled to May 25 to June 15.
Steve reminds that he is there for working, so operation during the day will be nearly impossible.

Steve, VK6SJ, announces via DX-World that he will be in Christmas Islands for working in May 7-25.

Operation in the evenings and early mornings only. FT-857D transceiver, barefoot with wire antennas and possibly a vertical. Operations will be focused on 80, 40 & 30m. Mainly FT8 operation.

VK9XX is the club callsign of the Christmas Island Amateur Radio Club, of which I am a member.

QSL will be via EB7DX.