Failure starting CM4 core project of STM32H7 when debugging using J-Link Ultra+ in CrossStudio 5.2.

Howdy!

We've got a dual-core STM32H7 project that debugs fine using 5.1.1 on both cores using the J-Link Ulta+. We launch two instances of the studio and debug each core as you'd expect, works great.

I recently went to evaluate 5.2, and noticed that we can no longer debug the CM4 core. Specifically, the executable image downloads to the target, and immediately after downloading it disconnects:
Loading target script file STM32H7_Target.js
Executing match part name script
Executing script MatchPartName("STM32H747XI_CM4")
Loading target script file STM32H7_Target.js
Preparing target for download
Executing Reset script FLASHReset()
Reset: Halt core after reset via DEMCR.VC_CORERESET.
Reset: Reset device via AIRCR.SYSRESETREQ.
Downloading 'STM32H7_CM4_Loader_rpc.elf' to STM32H7_CM4
Programming 1.9 KB of .load_section addresses 30000000 - 300007eb
Download successful
Verifying 'STM32H7_CM4_Loader_rpc.elf' on STM32H7_CM4
Verifying 1.9 KB of .load_section addresses 30000000 - 300007eb
Verify successful
Memory map 'after startup completion point' is active
Erasing 'MOBIUS_CM4.elf' on STM32H7_CM4
Erasing 508.8 KB of addresses 08100000 - 0817f387
Erasing 0.2 KB of addresses 0817f388 - 0817f47b
Erase successful
Downloading 'MOBIUS_CM4.elf' to STM32H7_CM4
Programming 508.8 KB of addresses 08100000 - 0817f387
Programming 0.2 KB of addresses 0817f388 - 0817f47b
Download successful
Verifying 'MOBIUS_CM4.elf' on STM32H7_CM4
Verifying 508.8 KB of addresses 08100000 - 0817f387
Verifying 0.2 KB of addresses 0817f388 - 0817f47b
Verify successful
Loading target script file STM32H7_Target.js
Preparing target for user application
Executing Reset script FLASHReset()
Memory map 'before startup completion point' is active
Reset: Halt core after reset via DEMCR.VC_CORERESET.
Reset: Reset device via AIRCR.SYSRESETREQ.
Memory map 'after startup completion point' is active
Target connection has been lost

Any idea what might be wrong? Could it be a target debugging setting file in our project for the CM4 core?

We don't have any CM4-core only projects to debug, or I'd try that.

Thanks!