Am I at a disadvantage not being an early applicant?

Universities (via UCAS) have to guarantee that all applications received before 15 Jan deadline get equal consideration.

That being said, you may or may not have a psychological advantage because admissions tutors may or may not feel that since there are many spaces left when you apply early they may give out some places more easily. Take this with a HUGE pinch of salt but from the different open events I've been to this has been the general advice. When sending it in January, the admissions staff have a huge pile to process.

Thank you! I’ll work to getting it sent off ASAP just to be safe