KB440703: After upgrading to MicroStrategy Secure Enterprise 10.4.7 (10.4 Hotfix 7), subscriptions for cube based reports get sent with non-personalized content

SYMPTOM
After an upgrade to Strategy 10.4 Hotfix 7, personalized subscriptions which existed before the upgrade get sent with non-personalized content, leading to end users receiving incorrect versions of their report. This issue is observed for subscriptions based on Intelligent Cube reports (view reports). Also, this issue is not seen for newly created subscriptions, but is seen with existing subscriptions. 
Users may receive either of the following errors trying to edit the subscription in Web as well: 

Error in report results 
User request is completed

or 

Error in job details
Your request could not be processed due to a server error. Please try again. If the problem persists, contact the server Administrator. User request is completed.

The following error may be observed in the DSSErrors log while attempting to edit the subscription:
 

2018-04-18 12:08:29.472-05:00 [HOST:HOSTNAME][SERVER:CastorServer][PID:1435][THR:4296][Kernel][Error] MsiWorkingSet::RebuildReportEx: report instance 0x1170032A8 get_Next return unexpected step 4100 during constructing result 
2018-04-18 12:08:29.472-05:00 [HOST:HOSTNAME][SERVER:CastorServer][PID:1435][THR:4296][Kernel][Error] MsiWorkingSet::ApplyDeltaXMLEx(): RebuildReportEx returns error = 0x800039BF

STEPS TO REPRODUCE 

1. In Strategy version prior to 10.4 Hotfix 7, create a view report based on an Intelligent Cube
2. Set a page-by attribute, for example "Region", with a default page-by selection, for example "Central"
3. Change the page-by to a different element, like "South", and create an email subscription. 
4. In a previous Strategy version (such as 10.3), triggering this subscription will send "South" data in the email. 
5. After upgrading the environment to Strategy 10.4 Hotfix 7, when triggering the same subscription, the content for "Central" gets sent instead.

CAUSE
This is a regression defect that was introduced with Strategy 10.4 Hotfix 7. 
ACTION
This issue is expected to be fixed in an upcoming Hotfix on Strategy Secure Enterprise 10.4.