That means at least 10 years of economic isolation and decay.
Members can officially join the EU any time. But practically, witth 27/28 members, the preparation period takes several years, and is timed now to coincide with the start or ends of the 5 year budget periods.
Juncker has said, for instance, that Serbia and Montenegro would join "by" 2024, meaning in election year 2024. This policy makes sense for the following two reasons
Joining in mid term means one of two things:
1. No MEPs for the new member, which is unacceptable.
2. An extta election for the new member, which could alter the majorities in the EU parliament and force a change of Commission Presedent and Commission.