From the looks of it, AMD will be announcing Vega 20 on Computex. Vega20 is a die shrink of the current model, and should be a 7nm part. It's mentioned that the new Radeon Instinct SKU (machine- deep-learning / enterprise GPU) would get a whopping 32 GB of HBM2 memory.
AMD itself has mentioned the existence of VEGA0 multiple ties away and earlier on mentioning that it would be launching in 218, according to their plans. According to a source of tweak town who spread this information, Vega 20 initially would just be a refresh of Vega 10 for the professional market. It is expected to get the same 64CUs as in Vega 10 and is fabbed at 7nm. Early this year it was already spotted in driver entries as well as a benchmark entry back in April, which also shows 32GB of graphics memory.
There's no word on anything for the consumer (gaming) side. For consumers, 7nm video cards base on Navi seem more viable. AMD has a press-conference this Wednesday.