Uh oh... may i point you do the fact that for at least one of those firms (it starts with an 'X', i'm not too familiar with the others), there in fact is a whole cloud service infrastructure (including synchronization, backup, and payment processing) that's _not_ hogging onto Google's service hosting train? That they have enough employees to provide updates _every Friday_?

Giving that most of Jolla's homework is done by other groups too (so-called 'communities') that care for the actual development of base OS, frameworks, and SW components, i can't see that they realistically have to care for building much from scratch, besides their (closed-source by the way) UI components and related integration.
Further, it was mentioned most of their guys came with an Maemo and N9 projects background; so it's even more moot thaey have to start from scratch. They are definitely able to leverage their expertise here and shorten their cycles.

And unless someone close to them can prove that they designed all of their hardware in-house, i bet there's a huge re-use of COTS board-level components going way farther that basic SoC reference designs.

And how many people are Jolla now, like 50? I bet they are steering towards 80. (sorry, can't be arsed to grep their Twitter musings for that...)
That's not a startup; size-wise.