TIBCO ActiveMatrix Platform 3.3.0 hotfix 24 has the below closed defect - 

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TAP-15771

In TIBCO ActiveMatrix BPM setup when upgrading a BPM Application, Administrator 
sets the "Prepare For Undeploy (PFU)" flag to "true" for the components' old 
versions. Previously, Administrator set the PFU flag back to "false" if 
"UNCONFIGURE" task failed during upgrade, thus blocking further upgrade. With 
this fix, Administrator doesn't set the PFU flag back to "false" even if 
"UNCONFIGURE" task fails, thus allowing further Application upgrade to proceed 
successfully.
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Prior to this fix, the following error is seen when upgrading a BPM application - 

TIBCO-AMX-ADMIN-012603: Not allowed to deploy the version 'x.x.x.xxxxx' of application 'xxxx' since the older version(s) are not in Preparing for Undeploy state: [x.x.x.yyyyy]. An upgrade from these versions may have failed in the past and that is why they are not in the expected state. If the upgrade to version 'x.x.x.zzzzz' had failed, you may need to force-undeploy it first (work items for this version will be cancelled).

This error can also occur when upgrading TIBCO ActiveMatrix BPM - documented here (https://support.tibco.com/s/article/TIBCO-ActiveMatrix-BPM-product-upgrade-may-fail-while-deploying-BPM-applications).