Thanks for that very interesting link, and I note Owain Glyndwr's quick response that reversion to Pitch Alternate may not have been necessary during the certification flights. Experience suggests he is usually right, in which case I infer that Normal Law and Alpha-Protection would have been retained, but alpha-max modified to a figure at or above Cz-max. Alpha-Floor would also be inhibited. If so, this would have the advantage that THS (pitch) up-trimming would cease at alpha-prot. That would make the exercise much safer than using Pitch Alternate, in which - as you have pointed out - the THS would continue trimming to the stall and beyond (as it did later on AF447).
To avoid a new AF447 and his autotrim problems, inhibit Alpha-Floor, and modify alpha-max at or above Cz-max...
prototypes*, would likely have had logical "hooks" linked to switches on the test consoles and possibly in the flight deck allowing for easy transfer between the different laws, modes
Why not put these switches on the consoles again to give observability and controllability
to the "ordinary" pilots (and gums who is not an ordinary pilot !) ?