On scope of GIPS standards relating to historical performance record

In reporting historical performance record section,

The CFA book mentions that firms may link non- GIPS- compliant performance to their GIPS- compliant performance provided that only GIPS- compliant performance is presented for period after 1 January 2000 and the firm disclose theperiods of non- compliance.

The CFA book also says that firms must not link non-GIPS-compliant performance for periods beginning on or after 1 January 2000 to their GIPS- compliant performance.

-----------------------------------------------------------------------------------------------------------------------------------------------------------------It seems conflicting to me… I would appreciate it if someone could explain to me the difference between the 2 sentences.

They’re saying the same thing: if you want to link performance that doesn’t comply with GIPS, is has to be performance prior to 1/1/2000. All performance on or after 1/1/2000 must comply with GIPS.

I thought the last sentence meant that all performance before or after January 1, 2000 must comply with GIPS. Thanks again for your help.