“01234567890123456789012…”というような長い文字列を一定の文字数で区切る必要があったので、簡単に処理を考えてみました。

Option Explicit

Public Sub Sample()
  Dim v As Variant
  Dim s As String
  
  s = "01234567890123456789012"
  s = s & "34567890123456789012345"
  s = s & "67890123456789012345678"
  s = s & "90123456789012345678901"
  s = s & "23456789012345678901234"
  s = s & "56789012345678901234567"
  s = s & "89012345678901234567890"
  s = s & "12345678901234567890123"
  s = s & "45678901234567890123456"
  s = s & "7890123456789012345"
  
  v = SplitStr(s, 10)
  Debug.Print s
  Debug.Print "----------"
  Debug.Print Join(v, vbCrLf)
End Sub

Private Function SplitStr(ByVal TargetStr As String, ByVal StrLength As Long) As Variant
'文字列を指定した文字数で分割
  Dim v As Variant
  Dim n As Long
  Dim i As Long
  
  n = 0 '初期化
  ReDim v(0 To Round(Len(TargetStr) / StrLength - 0.5, 0)) '切り捨て
  For i = 1 To Len(TargetStr) Step StrLength
    v(n) = Mid(TargetStr, i, StrLength)
    n = n + 1
  Next
  SplitStr = v
End Function

上記SplitStr関数は、指定した文字数で文字列を分割して結果をVariant型の配列で返します。