As a Challenge cache you will need to list in your Found It log entry the NINE (9) caches from 'your state' that qualify you for the 'Specialist' Find here. (Obviously) They are all of the rating of Difficulty 3, and the Terrain ratings required are: T1, T1½, T2, T2½, T3, T3½, T4, T4½, and T5. 

The minutes for this cache are:

Rules: 

1/ The TWELVE MONTHS is the time frame that you select. So it could be the first year that you started, OR, the most recent consecutive 12 months, OR any year in between. This DOES NOT have to be the same 12 months required for other in the Nine Tree Trail Series.

2/ This may be extended by a further SIX MONTHS for each additional  different Type of cache you are able to include in your list. SO, if you only use one particular Type of cache (no matter WHAT Type it is) it is still up to you to select the particular 365 consecutive days to get your list of caches from. BUT, if you choose (or are able) to include x 9 different Types of caches in your list each with a unique Terrain rating then you would have 5 years in the past of logging this cache to gain your list from - for example. And, if you use x 3 different Types then you would have 24 consecutive months, and so on.

3/ In your Found It log (or Note, if getting ready to come and find it), please include your State of Origin, and the time frame you are using for this cache. Then, for each of the x 9 qualifying caches: Terrain rating, GC code, Cache Name, Type, Date Found.
re 3/ a) Alternate ways to show qualifying caches, 4/ 'Wildcard', and 5/ Cache Owner exceptions see the D1 x 9 T State Challenge, GC5D8TN.

"So, you don't have a 'State of Origin' (or subsequently adopted a State), OR, your State doesn't have 'complement' of all nine possible Terrain combinations". Okay, if you otherwise qualify you are still welcome to log a Find for this one, but won't automatically be able to Find the Final State of Origin Challenge cache; but you are on your way to qualifying for the Victorian challenge cache. (Country of Origin is acceptable)

Below is a statistical representation of the quantity of Difficulty 3 caches that were active in the Australian States in September, 2014. As can be seen all the States have a full complement of D3 caches, however, for the CO's of the 'solitary caches' of Northern Territory and Tasmania any bordering state could be chosen for those missing Terrain combinations, ie, Queensland, South Australia, or Western Australia, or Victoria, and your State of Origin would still be accepted. PLEASE DON'T take these numbers 'as Gospel', as we all know that new caches will be added, and others Archived.
 

New South Wales: 1/5/13 to 30/4/14 (x 5 Types ->3 years)
T1, GC2EP8E, On Thin Ice, Trad, 6/7/13
1½ GC3MMKA, Sydney 50 Days in a row cache Challenge, Unknown, 30/5/13
T2, GCXHM2, Foreign Exchange, Multi, 25/11/13
2½ GC1KK89, The Search for Ned Kelly and the Stolen Treasure, Wherigo, 31/8/13
T3, GC1V44D, The Three Sisters EarthCache, E/C, 31/8/13
3½ GC1AA8, #17 Down The River, Trad, 27/1/14
T4, GC3M8NK, VHGC, Trad, 5/12/13
4½ GC4C0KW, 4B Playground no.5, Trad, 21/7/13
T5, GC2YY4Q, Adrenalin Addiction - Tree, Trad, 7/12/1

pprass