Hopefully, I can clear up the confusion.
The signature used at the factory had Orrefors (Designers name or assigned initial ie. Gate G or Hald H), initial for the type of production and on the engraved pieces the initials of the engraver, or the initals of the master glass blower, a number and sometimes the date.
After the early 1920's, I think they dropped including the glass master and engravers intials on the work. Gustaf Abels was a copper wheel engraver with fantastic talents
producing the Bacchus Bowl and many important pieces for the 1925 Paris Exposition.
I have not seen any work where he was designated as a designer.