Mode of issuance not updated when overlaying or updating record with existing SRS (Juniper bugfix)

Current situation or problem: The mode of issuance is mapped from position 07 of the LDR in MARC. When, for example, a record coded as a single unit is overlaid with a record coded as a serial, the LDR in the underlying source data would be updated as should the mode of issuance element in the instance.

This currently works as expected only when the existing record does not have underlying SRS MARC.

See attached documents for detailed explanation/illustration.

Leader description: https://www.loc.gov/marc/bibliographic/bdleader.html (note that position 07 is actually the 8th character, since the positions start at 00)

(Screen shots from Cornell Training, with HotFix #1 applied. And from snapshot.)

Steps to reproduce

1. Go to Iris bugfest or snapshot
2. Go to Inventory app
3. Filter by Source = MARC AND Mode of Issuance = single unit
4. Overlay with 226183297 (serial) or 19608982 (integrating resource)

OR

1. Go to Iris bugfest or snapshot
2. Create a new MARC bib record with Leader position 07 value = m unit via data import app
3. Then Update that record's Leader position 07 value = s via data import

Expected outcome: Leader position 07 value should change from m (single unit) to s (serial), no matter how the underlying MARC record's LDR/07 was updated. Changes from m to s should be reflected
1.) View Source,
2.) Edit quickMARC
3.) SRS
AND 4.) Inventory instance record should read serial for Mode of issuance value NOT single unit

Actual outcome: No change. Mode of issuance remains m (single unit)

Checks to make sure the Leader is handled consistently no matter what triggers the MARC Bib and Instance update: (add Testrail for each of these scenarios). Each of these assumes you're starting with an existing SRS MARC and Instance with one LDR/7 value and then each scenario covers a different way that the SRS MARC and the Instance could be updated, using a different MARC record with a different LDR/7 value. See sample record numbers above.

1. Job profile with a MARC modification action, but no Instance update or MARC update action. In the MARC modification action, just do something like Add a 500 $a Test note.
2. Job profile with a MARC update action, but no Instance update or MARC modification action.
3. Job profile with an Instance update action, but no MARC modification or MARC update action. In the Instance update, just change the instance status (since Instance update action also has an implied MARC update action in it)
4. Inventory single record import/Overlay action