I have high hopes for the SSMB EUV. I'm not an expert on particle physics, but from what I can tell, the SSMB EUV is basically a normal synchrotron that has a special array of magnetic undulators and laser that produce simulate the electrons to produce the EUV beam. But apart from the specifically built array of lasers and magnetic undulators that have to be situated next to the beamline, it's otherwise a normal synchrotron. It's not some completely brand new machine that has never been assembled before, with thousands of moving parts and a hundred thousand components. Synchrotron have been a thing since the 50s, and there's dozens of them in operation around the world today. And they can be build without ultra ultra specialised parts or companies.
And synchrotron and using them as a light source is a very mature field. Unlike ASML's EUV machine that can only really be assembled by them, around a dozen countries and companies can produce their own synchrotron and storage rings and have done so for decades. So there shouldn't be a bottleneck or lack of experience in building the majority of the synchrotron. The only bottleneck will be the special laser and magnet undulators used in actually producing the beam, but the main bulk of construction of the large machine shouldn't have any issues. Engineers and physicists also won't be in a short supply for the operation of the synchrotron, since they're a very mature technology at this point.
We might see the prototype SSMB EUV under construction get finished a lot faster than we thought, if 90% of it's construction is similar to the existing synchrotrons already in China. Hell, even if there's issues with the laser and the undulator, we might see multiple of the basic synchrotron built first and the laser/magnet undulators installed after the issues have been sorted out.
It depends on how hard it is to produce the special laser/magnet undulators how to control the laser/magnet undulators to produce the desired wavelength, but those are mainly controlled by computers/A.I which are getting better and better every year. Not to mention that undulators being used to control a synchrotron/FEL are also a very mature technology. Which is to say I can see the EUV light source being ready before the optical system, mask, EUV photoresist etc etc, with the main bottleneck being the other systems and how to integrate the EUV light source into a singular system. Like they build the synchrotron, have the laser and undulator installed, turn it on and with a few days of tweaking succeed in getting the desired EUV beam that they need.
Having the EUV light source be ready before the other components are ready could be beneficial, you could test your various photoresist, masks etc etc on the very same light source that they are designed to be integrated with.
Which would be funny if the most complicated part of a EUV machine, the light source, was the first part to be finished or one of the easiest and ASML chased after the more complicated LPP method after more than a decade just because the steady-state microbunching technique wasn't invented until 2010.