"unforeseen technical complexities"
In other words, the people who were responsible for the specifications fucked up. That seems to be a regular occurence within UK government structures.
If you are designing a framework which is supposed to work country-wide, you can't content yourself with the opinions of old farts who don't know how things work. You need to gather the needs of the people who will actually work with the product and are expected to deliver something.
I have 30 years of experience in designing and implementing software products. I obviously start with the stuffy ole farts who declare what they think is what they need. Then I go talk to the people who actually do the job, and make sure that the final product responds to their needs.
The old farts won't know the difference anyway.