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In order for call numbers to migrate to the subfields $h and $i in the holdings record, you must export your item and/or bib record call numbers based on the MARC tag of the call number field. Both the item call number MARC fields and the bib record call number MARC fields can be included in your item record export CSV file. If you only use call numbers from the item record, then you can simply export the MARC tags from the item call number fields. Subsequently if you only use call numbers from the bib record, you can simply export the MARC tags from the bib call number fields. In both cases, you will include the call numbers in your item export CSV file. If you use tags from both the item record and the bib record, you should export all MARC tags from both the item record and bib record that represent call numbers fields that you utilize.
When exporting these MARC fields based on the MARC tag, you must specify all subfields in the MARC field when exporting this MARC field. Let's take the following example: I want to retain call numbers from my bib record 090, 050 and 086 MARC fields. In some cases, there may be call numbers in item records that I want to take precedence over the above bib record call number fields. These are correspondingly the item record 090, 050 and 086 call number fields. The following image shows what each MARC FIELD export would look like. Note the inclusion of the subfields in the field export:
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Note that anything that is in the CALL #(ITEM) field will override all other call number fields. The CALL #(ITEM) field and the CALL #(BIBLIO) fields never retain the $h and $i upon export from Millennium and Sierra. If it is important to retain these subfields, you can choose not to export CALL #(ITEM) or CALL #(BIBLIO) at all.
If you do wish to include the CALL#(ITEM) field, you may do so, but turn off the setting under Settings | Create Lists | "Look up call numbers". Leaving this setting on will cause the CALL #(ITEM) field to be fully populated, and will subsequently override all other call number fields. If it is important to retain the $i in the holdings call number, I would suggest not exporting the CALL #(ITEM) field from Sierra/Millennium at all.
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