I wanted to use [StudyCompletionDate (0032,1050)] but since it is retired I would like to know the attribute to be used to determine whether a study is complete or is ready for Archival.
We are writing a archival solution for a PACS server, I would like to query the PACS server for the DICOM images that are marked for archival. I want to know if there is any flag that indicates that a DICOM image is marked for archival.
The preferred method for this type of operation would be through the use of the DICOM Instance Availability service, which is defined in DICOM Supplement 93. The beginning of the supplement describes several use cases similar to what you're discussing.
As far as just performing a DICOM C-FIND, and determining the study status, there's no real method to find out what you're looking for. The Instance Availability tag only tells if the study is Online, Nearline, or Offline. To see if its complete, and then you could monitor the Number of Study Related Instances tag to see if the number of instances is increasing. If its been stable for a configured amount of time, you could assume the study is complete.