Also keep in mind the time your film spends in the A solution. I've used TD 201 as well as Thornton and several other D-23 variants and have found the times recommended for the A bath to be too short for me. I did two rolls of 400 - Arista Premium and HP5+ - at six minutes in the A bath with intermittent agitation. That's the time that works for me; as they say, your results may vary.