According to insider sources, the RX 6x50 XT refresh would include RX 6950 XT, RX 6750 XT and RX 6650 XT SKUs, but no RX 6850 XT. The new GPUs are rumored to get upgraded with 18 Gbps GDDR6 VRAM and the high-end cards would also see a TGP bump.
https://www.notebookcheck.net/AMD-s-Navi2x-refresh-allegedly-launching-in-April-but-would-not-include-an-upgraded-RX-6800-XT-model.599985.0.html