OFS string for the multiple associated application

you have to use // to separate LD from LD-schedule data

Loans and Deposit contracts with Payment Schedules
An LD contract with a payment schedule requires the information for the linked application LD.SCHEDULE.DEFINE. This can be done by adding the field information for LD.SCHEDULE.DEFINE to the Loans and deposits MESSAGE DATA component, separated by ‘//’ (2 forward slashes).
When using OFS to update LD.LOANS.AND.DEPOSITS with LD.SCHEDULE.DEFINE, the GTS.CONTROL field on both versions must be set to 1, overrides and accepted and errors placed on hold.

When I remember correctly the LD.SCHEDULE.DEFINE version must have the same PGM.VERSION as the calling LD.LOANS.AND.DEPOSITS, when it's not present ,STD (for I) or ,STDAUTH (for A) are used (if they don't exist the vanilla LD.SCHEDULE.DEFINE will be launched).

e.g. if you use LD.LOANS.AND.DEPOSITS ,INPUT.NEW then define LD.SCHEDULE.DEFINE,INPUT.NEW and it will be called.

Found the description in LD User Guide :

Customising the Schedule Screen
The schedule definition screen is a standard application, LD.SCHEDULE.DEFINE that can be customised using the VERSION utility in the same way as with any other application.

In order to provide the flexibility of having an input VERSION that is unique or specially suited to a particular contract type, it is possible to create matching VERSION records for the main input LD.LOANS.AND.DEPOSITS and LD.SCHEDULE.DEFINE. This depends on what may be called the VERSION extension; the part of the id after the application name starting with and including the comma (i.e.,COMM).

For example a commitment contract that needs no P schedules could be simplified and use a VERSION contract LD.LOANS.AND.DEPOSITS,COMM. A schedule input VERSION called LD.SCHEDULE.DEFINE,COMM would be invoked automatically as the VERSION part of the application is the same.

The rules for use are:

If a VERSION extension for LD.LOANS.AND.DEPOSITS exists on file for LD.SCHEDULE.DEFINE, then those VERSIONS are used.
If a VERSION extension for LD.LOANS.AND.DEPOSITS does not exist on file for LD.SCHEDULE.DEFINE or no VERSION is used then
- LD.SCHEDULE.DEFINE,STD is used for Input function
- LD.SCHEDULE.DEFINE,STDAUTH is used for authorisation function.

These VERSION records are released as standard and should not be modified.