Originally Posted by
CO_Nonrev_elite
... Are there any workarounds to allow you to SDC to the exact same flight the day before. ...
The only realistic hope is to show up at the airport and see if an agent will do this. It is clearly outside the rules and probably going to be even more difficult with from a non-domestic location and trying for the business cabin (as upgraders may fill the presently available seats).
A more realistic approach is to do a 1-stop routing that meets the SDC requirements.
Prior discussions earlier in this thread on this may be of some help.