(Mis-)Behaviour of Bank Payment Edits

I noticed that when I edit journal entries, like update a memo, the existing entry is modified.  However, when I edit a Bank Payment, even just the memo, a new entry is created with a new entry number.  Although inconsistent, this doesn't bother me too much since it is only a number, however, the change also results in any attachments being dropped.  Since I attach copies of invoices to many payments, now I must re-attach the document anytime I edit and, ideally, to keep things tidy, remember to delete the old attachment which is otherwise just floating around without a real home.  This of course is worsened by the fact that is much less straight forward to attach documents under Setup (as is required after an edit) than after creating a new entry.

Would it not be possible to keep the same entry number so attachments are maintained?  Or, if not, automatically transfer the attachment to the new entry and delete the attachment record of the old?