いつかの ... => Previously N4
Time
ぶり => style; manner; way​ N1
~こと請け合い => I guarantee ... N1
Happens next
ぶりに => for the first time in (period of time) N3
合う => do something together N3
~且つ(かつ) => and N1
Line up, list
を中心に => focused on; centered on~ N2
いつしか => before one knows N2
Accept, agree
いつか => Since when (Don't know) N4
Time
たぶん => Maybe... N4
Speculation
いつか ... た => Formerly (At some point) N4
Time
いつか(は) => sometime; someday; one day N4
Future time