[Mp4-tech] [Audio] Non-sbr streams in HE-AAC decoder

[Haricharan L.]

Hi Experts, 
According to HE-AAC spec, the max AAC sampling frequency for non-SBR streams (AAC only streams) for levels 2/3 decoder is 48kHz .
(Table 1.8A of N5570 doc)
1) Is my understanding right? Why is such a restriction imposed? 
2) If an HEAAC decoder, decodes AAC-only streams with sampling freq greater than 48kHz, will the decoder be considered not compliant to HEAAC spec? 
Regards, 
Hari