Hi there - First congratulations on your achievements thus far! And I know you are going to enjoy your semester in Austin -- I graduated from UT. I do not think that consulting firms would look down on a year off, as long as you are fully utilizing that time. It sounds like you will have an internship, which will be great. Be sure to keep yourself working or doing things worthwhile during that time. I'm sure during your interviews they will ask you about it, so be prepared to answer questions about why you took the time (i.e. you wanted time to have explore the internship, you were seeking personal growth experiences, etc), what you did with the time, and how that year has put you at an advantage to your peers because you've had x number of experiences.
That being said, I would suggest reaching out to your career counselor or any contacts you might know at consulting firms in the UK to get their opinion as well. If your classmates also have the same pressures and responsibilities they might expect you to also be prepared for the exam this year. However, if you do have some great experiences in the year off that will better prepare you for work it can't hurt.
Best of luck!