"Established at Preliminary Level"??

In looking over the T3D requirements, I've always seen that you can either get four NQRs OR be "established at preliminary." Does anyone know what the heck does the USEA mean by this? I ran two prelims (only one of which was an NQR thanks to our not-so-kind dressage judge at Penny Oaks '11) with my horse in 2011 before he died, but is that enough to "establish" me?

I mostly ask because my current horse needs one more NQR to run at Indiana if I view my qualifications from a four NQR standpoint. I'm sure we can get it done, but as we all know, crap happens. So it'd be really nice to know that we're already qualified between our three NQRs together and my experience running my 2 prelims.

Basically it means that you have to be qualified to compete at prelimary level (which if you have competed within the time period counts, of course). So you are good if you did those prelimnaries within the last two years.

EV105 QUALIFICATIONS.
For certain levels of competition, horses and riders must meet qualifying requirements. Those requirements are detailed in Appendix 3.
1. ESTABLISHMENT OF QUALIFICATION.
When a horse and/or rider obtains a qualifying result (QR) at a level, then they are “established” (qualified to compete) at that level. This “establishment” lasts for the remainder of the current calendar year and the two succeeding calendar years. Note: Re-establishment as in paragraph 2 (c) below is required when the time period has expired.
2. EXTENSION OF ESTABLISHMENT (maintaining qualification)
a. The “establishment” may be extended by obtaining QRs at other events of the same level within the time period stated above, each extension remaining effective for the remainder of
the current calendar year and the succeeding calendar year.
b. If no such extension is achieved, the “establishment” at that level expires.
c. Establishment may be re-acquired by achieving 2 QRs at the next lower height level of competition within any 12 month period following loss of qualification.
3. LOSS OF ESTABLISHMENT. (Preliminary Level and up)
In cases cited in EV105.3, only penalties assessed during the cross-country phase of competition apply.
a. A horse that is eliminated, for disobediences in the cross-country phase of competition, three times within any 12 month period loses its establishment to compete at the higher level
at which the elimination occurs.
b. A horse that falls in the cross-country phase of competition 2 times in any 12 month period loses its establishment to compete at the higher level at which a fall occurs.
c. A rider who falls in the cross-country phase of competition from the same horse 3 times in any 12 month period will cause the horse to lose its establishment to compete at the higher
level at which a fall occurs.
d. Having lost establishment, a horse may be re-established by achieving 2 QRs at the next lower height level (e.g., loss of establishment at the CCI2* level requires re-establishment at
the Preliminary Level) within any 6 month period and no sooner than one month following the loss of establishment.
e. Any combination of occurrences in .a, .b, or .c above for a total of 3 occurrences will resultin loss of establishment.
f. At the Advanced, Three Star and Four Star levels, riders who are subject to the provisions of this rule may petition the USEF Eventing Credentials Committee for review and redress.