There's nothing confirmed, AFAIK.
Looking at prior "X" lineups though, there's never been a "refresh".
Typically, you have 4 CPUs or so on the HEDT platform.... and that's that, until then next releases.
So, give we've already got 7 chips in the "Skylake-X" line (excluding the two, pointless, EOL, "KabyLake-X" chips)..... i wouldn't anticipate much more than the addition of the 22core chip at the top of the stack.
We *might* see one other in the "mainstream" space (thinking 8-12 core, $500-$600 range).... but I wouldn't outright expect anything more than the addition of the 22core chip.