Is it delulu to register for the philly marathon before doing a half?

Itching to do a half marathon after doing broad street this weekend but the next one that really interests me would either the philly distance run or the philly half. The philly half is in 6 months and part of me is like if I’m gonna wait 6 months for another race, isn’t that enough time to train for a marathon? Is that crazy? Broad street was my first time running 10 miles and I felt amazing honestly. If I did the half instead of the marathon, I could just get super fast this summer and do a marathon sometime in the spring maybe but that’s a whole year from now. Thoughts and advice appreciated.