I know what you mean. The question is how to do it simple? How to shift the LE without touching it with flip-flops? ... you can do the "pulse" from LRCK, but the result can be jitter from propagation delay.It is most important to understand that finishing register loading and LE changing state from 1 to 0 is happening almost instantly. And that is the cae ONLY if Rigt Justified format used... Because of that only LE in this case has to be precise but other syncs are also important. And Jitter in time can have max afect.
IF you left few bits of BCK when registers are already loaded, and LE stays in place, jitter could not be from that importance and DAc have much more time to "rest" and go to the conversion.
That is Whu Time Simultaneous format did this and Pacific Microsonic done the same - left blank sertain amount of BCKs prior to LE change state.
Only if we have 32 bit word we simply have to use all 32 bit for channel word and make it like pure Right Jusified format.
In all other cases we dont have to.
For 24 bit word we have 4 bits at each side of the word and 4 bits before each command to conversion.