Some info about the conversion from SAP ERP 6.0 to S/4 HANA 2022 I used recently and find it useful.
There was times and years where you can easily check you SAP ERP version by going in the SAP GUI menu: System -> Status -> SAP System data. And by reading certain component version you have the info. Like below:
|2016||SAP ERP 6.0 EHP8||NetWeaver 7.5 (7.50)||6.18||2027|
|2016||SAP S/4 HANA 1610||NetWeaver 7.51 (7.51)||S4CORE 101||2021|
|2017||SAP S/4 HANA 1709||NetWeaver 7.52 (7.52)||S4CORE 102||2022|
|2018||SAP S/4 HANA 1809||NetWeaver 7.53(7.53)||S4CORE 103||2023|
|2019||SAP S/4 HANA 1909||NetWeaver 7.54(7.54)||S4CORE 104||2024|
|2020||SAP S/4 HANA 2020||NetWeaver 7.55(7.55)||S4CORE 105||2025|
|2021||SAP S/4 HANA 2021||NetWeaver 7.56(7.56)||S4CORE 106||2026|
|2022||SAP S/4 HANA 2022||NetWeaver 7.57(7.57)||S4CORE 107||2027|
Check this article: https://answers.sap.com/questions/707755/how-can-i-see-if-my-sap-s4-is-a-1709-or-a-1809-rel.html
The problem I faced in recent S/4 version 2022 this does not work anymore. And as in the article someone said “This screen does not appear any more in 1909 release…“
More info how to restrict info in the System / Status in OSS Note: 2658772 – System -> Status: Restriction of the available information
The solution is to view the versions of SAP / HANA / ABAP using Function Module: OCS_UI_DISPLAY_PATCH_LEVEL in SE37. Once you know the S4CORE version you can check above what exactly is you HANA release.
A collection of good articles about the ERP to S4 conversion
SAP S/4HANA System Conversion – Custom code adaptation process (by Olga Dolinskaja)
Check your customer specific ABAP code via ABAP Test Cockpit (ATC) for compatibility with SAP S/4HANA as described in SAP note 2190420.
See also OSS Note 2241080 – SAP S/4HANA: Content for checking customer specific code.