I'm due to fly to JFK next Thursday on the BA115 from LHR, however i'd like if possible to take an earlier flight as it would mean that I get to my destination at a much more reasonable time.

Now in light of the current travel chaos what with the bad weather and holidays etc, what are my chances of doing this without a penalty?? I'm quite flexible in terms of what flight I take, so long as I get there earlier in the day

Is it worth me contacting someone from BA on here as I can't get through to BA on the phone?