I applied for a fellowship with the help from a potential PhD supervisor back in October. I had to write a research proposal and personal statement. The professor helped me edit it, and build the research proposal. I have been notified I have passed to the next round of the fellowship selection, but won't know the final result until march.
Meanwhile, I have applied to other PhD programs. I have been offered a place at one rotation phd program, which is fully funded. I really like the program and would prefer to go there. This program is also asking me to send them my decision by the end of this week.
How can I go about telling the first professor I have decided to play it safe with a fully funded offer rather than wait for a fellowship I don't know I will win? I feel really bad because they put the effort into helping me write the research proposal and personal statement. I also don't want to be burning bridges and hindering my academic career.
Most questions on this site mention being honest and overall fast with my response. I wanted to ask my question, though, since I went through the process of applying for the fellowship with the professor, and I feel that makes the rejection a bit more delicate.
Thanks in advance for any advice.