There is no conceivable way in which an estimate of 5.5 years in a non-physical process is anything other than bullshit. If you're estimating paperwork in years

There is no conceivable way in which an estimate of 5.5 years in a non-physical process is anything other than bullshit. If you're estimating paperwork in years, then you're already giving enormously rough estimates. 5 years maybe would have made some sense, but .5 years at that scale is just a way to make a gut feeling sound precise. Even more importantly, the process of acceeding to the European Union is a political and economic process. The pace at which such things go and the exact requirements are in a constant churn. Today you might need some paperwork, tomorrow some other. You might meet all the technical requirements but not be accepted, or you might not meet all the technical requirements but exceptions can be made, all at the whims of other states' current leaders. Long-term estimates are not even close to plausible for such a process.