This will depend on your acquisition method. Paid search will give registrations and potential upgrades almost instantly, but it takes time and investment to fully optimise a campaign at the right costs.
Paid Search will give you a direct response quickly and you will receive clicks through to your landing page, as well as potential basic/full sign ups.
However, it takes time and investment to fully optimise a campaign to ensure that you acquire a basic member at a low enough cost.
The larger your initial budget, the sooner you will collect enough data to draw any real conclusions, thus allowing you to optimise your campaigns effectively.
As a rough estimate, you should aim to break even by month 3 and be making a profit by month 6.