Upgraded customization's user fields aren't populating in the grid - acumatica

Question

I have a customization to add user fields to the Employee Time Card screen (EP305000) grid area that's been working through several versions / upgrades - but now in version 20.102.0015 it fails to bring in the data into the user fields.
The user fields are defined as follows:
public class EPTimecardDetailExt : PXCacheExtension<EPTimecardDetail>
{
#region UsrStartDate
public abstract class usrStartDate : IBqlField { }
[PXDBDateAndTime(DisplayNameDate = "Start Date", DisplayNameTime = "Start Time*", UseTimeZone = true)]
//[PXDBTime(DisplayMask = "t", InputMask = "t")]
[PXUIField(DisplayName = "Start Time*")]
public virtual DateTime? UsrStartDate { get; set; }
#endregion
#region UsrEndDate
public abstract class usrEndDate : IBqlField { }
[PXDBDateAndTime(DisplayNameDate = "End Date", DisplayNameTime = "End Time*", UseTimeZone = true)]
//[PXDBTime(DisplayMask = "t", InputMask = "t")]
[PXUIField(DisplayName = "End Time*")]
public virtual DateTime? UsrEndDate { get; set; }
#endregion
#region UsrRelatedCase
public abstract class usrRelatedCase : IBqlField { }
[PXDBString(10)]
[PXUIField(DisplayName = "Related Case*")]
[PXSelector(typeof(Search2<CRCase.caseCD,
InnerJoin<PMProject,
On<CRCase.customerID, Equal<PMProject.customerID>>>,
Where<PMProject.contractID, Equal<Current<EPTimecardDetail.projectID>>>,
OrderBy<Desc<CRCase.caseCD>>>),
typeof(CRCase.caseCD),
typeof(CRCase.subject),
typeof(CRCase.createdDateTime),
typeof(CRCase.caseClassID),
typeof(CRCase.status),
typeof(CRCase.contactID),
typeof(CRCase.ownerID),
DescriptionField = typeof(CRCase.subject))]
//typeof(CRCase.status),
//typeof(CRCase.priority),
//typeof(CRCase.severity),
//typeof(CRCase.caseClassID),
//typeof(BAccount.acctName),
//Filterable = true)]
public virtual string UsrRelatedCase { get; set; }
#endregion
}
The values are in the database - they save correctly - but they won't show up in the grid.
Any idea why this would happen?

Answer 1

The solution to this was provided by Acumatica support.
In my customization, I was creating a Cache Extension for a 'Projection' DAC, namely EPTimeCardDetail. The solution was to create an extension of the DAC which represented the actual table to which the user fields were actually added, which is PMTimeActivity.
Once I created the Cache Extension to PMTimeActivity, the problem was solved and the values were displayed in the grid.
It is unknown why this worked fine in previous versions.