1. Bach - prelude & fugue BWV893 in b minor (5")
2. Beethoven - sonata no.17 in D minor op.31 no.2 ( tempest ) (25")
3. Chopin - nocturne op.27 no.2 (5-6")
4. Fazil Say - paganini jazz (4-5")
Good luck with your programme planning. You didn't (plan to) take DipABRSM or ATCL beforehand? When will you take the LTCL exam? 2016? 2017?
Tempest is a very popular choice. However, you should note that long repeats should be avoided (see exam guidelines and regulations). You should discount/re-clock the playing time. If you play without repeats and you still need 25 min., then either you are so genius to be able to bring out something very special or you are simply playing too slow! Without repeats, most candidates would finish the work in 19-20 min.
Now, if you will definitely keep Bach and Beethoven, then you need to think: (a) add the 5th work to meet the min playing time requirement (38-43 min), (b) replace Chopin, or Say, or both with 1-2 longer work(s). FYI, I passed my LTCL and FTCL by self-learning. The 4 works in my initial LT plan are 100% different from my final programme. You need to keep your choices open for a while. Shortlist a few "prospect ones" from the syllabus. For the time being, I urge you not to buy the original scores of Fazil Say Paganini Jazz but to research the syllabus. Youtube, public/university library (borrowing scores & CDs), ismlp.org, scorser.com are useful resources.
You don't need to play in the sequence of periods, though it's the norm of many candidates.
If you didn't keep learning and practicing the piano during these 4 years (since your Gr 8 exam), then you ought to pay more effort to prepare this time. The gap between Gr 8 and LT is fairly wide.
Good luck!