[NTG-context] Question about spacing of some math symbols

Hi all, While testing some XITS symbols, I was wondering about the spacing of the following symbols: \setupbodyfont[xits] \starttext $$a < b$$ # reference $$a ⨼ b$$ $$a ⨽ b$$ $$a ⪝ b$$ $$a ⪞ b$$ $$a ⪬ b$$ $$a ⪭ b$$ \stoptext Not sure about the first two, but I think the rest should be mathrel (additionally, does anyone knows a definite Unicode reference for such proprieties?) Regards, Khaled