There is a website that lists most Heathrow movements which goes back a long way including 1995. I just had a look for 15/1/1995 but unfortunatly BA001 was not listed, for that day. If you go have a look yourself, you may be able to look at the next day, or maybe even the same day if BA1 was an early morning departure to see if the return flight was listed. Maybe someone else can help out with the rotation schedule so you can identify what the return flight would have been. An assumption would be BA2.
The website is located here:
http://www.lhr-lgw.co.uk/groupfiles/newlhrarchives.htm