Questão jurídica principal
Whether the IV decision of 20 July 2016 was void because it ignored later developments after the 2013 pension decision.
Decisão extraída
No. The defect was serious but did not reach the high threshold for nullity; the decision remained appealable and became final when not challenged.
Fundamentação extraída
Nullity is reserved for especially grave, obvious defects, typically lack of jurisdiction or extreme procedural errors. The delay and resulting incomplete factual basis did not justify treating the decision as void.