I am getting JzosUtility.executeCommand errors - EDC5045I The operation attempted could not be performed because the file was open. Is there a missing pre-req?

Recently migrated to RTC 6.0.6, and upgraded the Buildsystem Buildtoolkit to v6.0.6, and started getting JzosUtility.executeCommand errors - EDC5045I The operation attempted could not be performed because the file was open.  Is there a missing pre-req? 

This feels like a new problem introduced with the upgraded toolkit:

2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00737) da('TDAPM.GM610KL.LINK(AGMATM64)') shr msg(1)
2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00738) da('TDAPM.GM610KL.LINK(AGMZDUMP)') shr msg(1)
2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00739) da('TDAPM.GM610KL.AAGMINST(AGMJ5REC)') shr msg(1)
2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00740) da('TDAPM.GM610KL.AAGMINST(AGMJ7ACC)') shr msg(1)
2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00741) da('TDAPM.GM610KL.AAGMINST(AGMJ3ALO)') shr msg(1)
2018-09-19 08:45:14: JzosUtility.executeCommand: alloc fi(ZEE00742) da('TDAPM.GM610KL.AAGMINST(AGMJ6APP)') shr msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: free fi(ZEE00719) msg(1)
2018-09-19 08:45:15: Update(save) ISPF statistics for TDAPM.GM610KL.C(AGMAKFKA)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00743) da('TDAPM.GM610KL.LINK(AGMZ$WTO)') shr msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00744) da('TDAPM.GM610KL.LINK(AGMALOG)') shr msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00745) da('TDAPM.GM610KL.LINK(AGMZXZAP)') shr msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00746) da('TDAPM.GM610KL.LINK(AGMATJAV)') shr msg(1)
2018-09-19 08:45:15: Update(save) ISPF statistics for TDAPM.GM610KL.C(AGMALOG)
2018-09-19 08:45:15: JzosUtility.executeCommand: FREE fi(ZEE00735) msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: free fi(ZEE00720) msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00747) da(TDAPM.GM610KL.CJSRC) SHR REUSE msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: alloc fi(ZEE00748) da('TDAPM.GM610KL.LINK(AGMAPI31)') shr msg(1)
2018-09-19 08:45:15: Remove TDAPM.GM610KL.CJSRC(AGMATEMS)
2018-09-19 08:45:15: JzosUtility.executeCommand: free fi(ZEE00722) msg(1)
2018-09-19 08:45:15: //DD:ZEE00739: fopen() failed; EDC5045I The operation attempted could not be performed because the file was open.; errno=45 errno2=0xc00b0445 last_op=43 errorCode=0x0
2018-09-19 08:45:15: JzosUtility.executeCommand: free fi(ZEE00739) msg(1)
2018-09-19 08:45:15: JzosUtility.executeCommand: free fi(ZEE00723) msg(1)