Remove old attachments when submitting bids to the new round's bid

Summary:

Our client reported an issue with attachments in sourcing with all submitted bids, which include attachments (e.g. PDF bids, XLS files, etc.). It is noticeable that all old attachments from previous rounds are transferred to new round. Therefore, if the supplier does not delete the old attachments and only adds new ones, then all the old attachments from the previous rounds and those from the current round are transferred to the next round. All the attachments (that is, old and new) have the date of the current cycle, therefore it is very difficult to distinguish them from each other.