In a patch for the Linux drivers for AMD gps, a reference was found to Vega 20, a series of gpu’s unannounced to date. It is probably the successors of the current Vega chips, such as the Vega 56 and 64.
The reference can be found in the logs on the Git page of Freedesktop . Six IDs are mentioned, suggesting that AMD works on such a number of gpu’s based on Vega 20. For the Vega 10-series nine id’s were made of which seven were eventually used, among others for the Vega Frontier Edition, Vega 56 and Vega 64.
According to previous rumors ] AMD plans to release the new generation of Vega cards in the second half of 2018. The video cards would be equipped with up to four stacks of hbm2 and up to 32GB of ram. Last year Vega Frontier Edition came out about three months after the first signs of Linux drivers appeared.