If this was a public company I would put my tin foil hat and believe that it's a quick buck scheme to boost CEO pay. A short sighted action that is not in the shareholders interest. But I guess that's not the case? Who knows...
At this stage of the product lifecycle, free users are unlikely to ever give you money without some further "incentives". This shouldnt be news by now, especially on HN.
If you're production service is relying on a free-tier someone else provides, you must have some business continuity built in. These are not philanthropic organisations.
