I recorded Heavylift IL76 RA-76401 many times between 26/11/96 and 5/3/97, but the photo looks like it was taken in the summer (green leaves on trees). RA-76842 I then recorded several times 7/11/97 to 15/4/98. The only record I have of their IL76's during summer is RA-76401 on 16/9/97. None of my sightings included Belfast G-BEPS on the same day as an IL-76. So no useful answer from me - some time between 1996 and 1998.....
I would put money on this being RA-76758, as it has the Oil Spill Service Centre titles. It was the first IL76 we got.....