The leaker Longhorn (@never_released) has information on the A14 and A14X.
Furthermore, the A14X is apparently scheduled for 2020:@never_released said:Apple A14 names 'cause it's never too early:
Apple A14: t8101
Apple A14X: t8103
Also mentioned is a list of Apple CPU codenames.@never_released said:The good news for you: Apple A14X exists, so come back next year.
@never_released said:Tempest ASC2, ASC3, ASC4
Chinook ASC2, ASC3, ASC4
Lightning, Icestorm, Firestorm
Tempest and Chinook are for the A12 while Lightning is for the A13 (along with Thunder). Perhaps Firestorm and Icestorm are the cores in the A14?@never_released said:Firestorm and Icestorm aren't for 2019