On my Atala, my Cyclone Mk-II short cage derailleur has no problem shifting up onto my 30t rear cog. Not quite the same derailleur, but I imagine the geometry is quite similar.

In fact, with the B-screw set totally loose (like, the same as if you unscrewed it completely and removed it), the top pivot never even moves as it shifts across my 13-30 cassette. Makes me wonder why this derailleur even has a top pivot.