AVAILABILITY_CHECK Function module not working after upgrade

[#1]

Dear Team,

After upgrade to S4 HANA 2021 FPS01 Function module AVAILABILITY_CHECK doesnt provide Sales order number in DELNR field anymore.
Please refer to the Test data directory named "..."

We tried replacing the fm with S4 FM AVAILABILITY_CHECK_S4, however this FM doesnt have a parameter P_ATPMATX (like in previous FM), this parameter provided us ENDWZ (End of replenishment lead time)
Pease refer to the Test data directory named "..." (also)

Can you please either provide a correction for FM AVAILABILITY_CHECK to give SO number in DELNR field
OR
Can you please tell us which field in S4 FM gives us ENDWZ.

Regards

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[SAPSupport · Accepted solution]

Dear customer,

Please have a look at this blog from SAP colleague:

https://blogs.sap.com/2013/09/14/use-of-standard-sap-function-modules-in-custom-development/

Thank you for your valuable cooperation and attention.

Best Regards,
SAP Product Support