AVID Sibelius File Splitting (Beethoven Missa Solemnis)

Title: Split one Sibelius file (Beethoven Missa Solemnis) into 5 separate movement files

Overview:
I have a single Sibelius (Sibelius Ultimate) file containing the complete Beethoven Missa Solemnis — all 5 movements in one file. I need it split into 5 separate .sib files, one per movement, each a clean standalone score that opens and plays back correctly on its own.

The 5 movements:

Kyrie
Gloria
Credo
Sanctus
Agnus Dei

Deliverables:

5 separate .sib files, named
Beethoven_Missa_solemnis_1_Kyrie.sib,
Beethoven_Missa_solemnis_2_Gloria.sib,
Beethoven_Missa_solemnis_3_Credo.sib,
Beethoven_Missa_solemnis_4_Sanctus.sib,
Beethoven_Missa_solemnis_5_Agnus_Dei.sib.

Each file must contain only that movement's music, complete and correct (all instruments/voices, lyrics, dynamics, tempo markings intact).
Each file must open cleanly and play back from bar 1 (correct tempo, key, time signature carried over).
Each file must export as a video without error (File → Export → Video).

Requirements:

Must own and be proficient in Sibelius Ultimate.
Experience splitting/extracting movements from large scores.
Attention to detail — no dropped bars, lost lyrics, or broken playback at the movement boundaries.

To apply: Confirm you have Sibelius Ultimate and briefly describe how you'd split a multi-movement score into separate files.

Notes: This is a small, well-defined task. If done well, there is likely ongoing similar work (splitting and preparing other multi-movement choral scores).