Hi Cryo2018,
Hopefully some wiser heads will chime here as well as my Bonsai newbie advice.
I have 3 of these seedlings and they have a blend of blue and more green.
So my advice is that IF your tree is growing strongly, ie lots of new growth elongating in your previous season then it will handle a root prune happily. Probably 1/3 off bottom of roots then “half bare root” rest of rootball. Then next repot do the HBR etc in a few years etc.
I haven’t experienced this yet but I have read a few threads that if you prune TOO MUCH roots off, your tree will sulk, lose all its needles. But that is usually short-lived as if tree is strong it will push new load of needles.
Hopefully either/both @Adair M or @JudyB might drop by for some advice also.
And FYI, use the search function on this HUGE website and you gets loads of info on Cedrus etc.
Hope that helps, and I don’t class my babies as strong enough to do any much root work when my Winter rolls around.
Charles