Bank angle ?!?!?
Please post a picture in level flight and one more complete picture showing the bank angle during this situation. I think there is a modification for some a320 family a/c showing a alpha prot above VLS.(consult your engineering department).Anyway I think I can have the same result if I manually increase the bank at this altitude. If the situation is not created on purpose (bank angle + spoilers) a check of alpha parameters AOA and aoa3 could clarify if one(or more) AOA probe is blocked or giving erroneous inputs.