Time for some official confusion here!! We can vouch for the fact that Windows 10 Mobile original plans have very much accommodated all Lumia devices including those with bare minimum specifications like Lumia 530. Though many have faced issues in installing windows 10 Mobile on Lumia 530, but many succeeded too and that includes us, but sadly we don’t have a Lumia 530 right now to demo. Even the official supported phones list for Insider preview still has Lumia 530 in it.
But some confusion has been created by the list of phones that are supposed to get Windows 10 Mobile first and the mention of “8 GB of internal memory required” on “Windows 10 coming soon pages“.
But we still think this requirement is valid for only the devices that will be the first ones to get Windows 10 Mobile. If you check the screenshot carefully, Lumia 635 with 1 GB RAM is also included in the first list. Though Lumia 635 with 512 MB RAM can run Windows 10 Mobile fine. So, no need to panic, as Lumia 530 is still supported like the devices with 512 MB RAM, though they are not included in the first list.