Feb is the tail end of peak travel time to India. Peak travel to India has been increasing in duration. Paid business class is full on most airlines during peak times this year (Nov 2003-Feb 2004 and July-Sep 2004).
What are your other constraints? Do you have to go non-stop to DEL or can you connect through other cities. If you can use BOM as connecting point, AA has good award to BOM on Swiss in business class.
LHR-DEL is a tough segment (sometimes abundant availability and sometime nothing for weeks). BA has been asking Indian govt forever to give it more rights to fly to India. However, the problem is that India feels that BA has been seeking a one-sided deal by offering the Indian carrier (AI) really poor landing slots at LHR. I am not sure that this will get resolved soon, so you are not going to see much capacity growth on LHR-DEL on OW.
CX will likely increase capacity to India next year. If you are looking at Winter schedule watch for CX announcements (Indian govt offers a limited open-sky agreement during peak season and CX has applied). Also, there are efforts by AI to fly to US West Coast and usually this is routed via HKG. This means by Feb CX may increase frequency.
As other have suggested, you are better off looking at other cities and connecting domestically using advanced purchase fares on Jet, Sahara or IA (upto 75% off in Coach and about 50% in business).
India is poorly served by OW (especially South India - but your interest is DEL). Star has many, many carriers offering a lot more frequency to India and they are only expecting to increase capacity further in the coming months.
Another twisted option if you do not have a choice may be to get an award to BKK (JFK-HKG-BKK on CX) and connect by paid segment to DEL (lot of competition on DEL-BKK if you go through ethnic TAs)