This is kind of a pointless post, OP. CG specified the farmable node schedule in the Era update post.
1) Silvo was supposed to be farmable this week. Instead we got a repeat message about him being in shipments, which is clearly a mistake. I'm annoyed, but not surprised that CG are missing things (Silvo farmable, the last GC quest) just ahead of the biggest update SWGOH has ever had. They fixed the GC quest issue, they'll probably fix Silvo as well.
2) Marquees up to Zuckuss will probably stick to the old schedule (farmable a few weeks after release) but Era marquees, starting with upcoming 6, will be on a new schedule: as I understand it, all 6 will be released at the same time (with the big update next week) and once the Era ends, all 6 will become node farmable at the same time, ~13 weeks after their release.
So, if you don't hit a high enough Era level on a character during their Era to bring them up to 7 stars, you will be able to begin farming shards 13 weeks after their release.