We have an alpha site which is very different from the beta site we plan to launch in a few months. On 5th July we briefly launched the alpha site on our intended domain for the beta site (example.com) but quickly (on 16th July) decided we would move the alpha site and put up a holding page on the main domain example.com so that users are not confused when we launch our rather different beta site there.
Given that the alpha site is geo-specific, we felt the best location for it would be example.co.uk, but, because we want to eventually redirect users typing in example.co.uk to example.com, we put the alpha site on a subdomain: sub.example.co.uk.
Initially we saw organic traffic gradually increasing, especially after submitting a sitemap. However, since 12th August our organic traffic has dropped to almost nothing (~2 visits per day). This is despite having over 100,000 pages indexed. 12th August coincided with a request from webmaster tools to re-verify example.com.
So, to summarise, we have a site on a subdomain whose main domain homepage (only) is redirected to another domain. Is there a reason why the subdomain pages will not rank, despite lots of pages being indexed? Would we improve our rankings and traffic by moving the alpha site to a completely different domain rather than using a subdomain? Is there a requirement for a main domain homepage to be an integrated content page in order for its subdomains to rank? Or could there be another reason for our lack of organic traffic?
Any thoughts greatly appreciated.