Last month Gunn said they were doing a day and a half of pickup shots. Which I assume is a different that reshoots.
No, pickup shots can include either reshoots or new material, anything that's deemed necessary to refine or improve the film after principal photography ends.

What Are Pick Up Shots in Film — Definition & How They Work
Pick up shots are filmed after principal photography has ended. Pick up shots are shot for a variety of reasons both logistical and creative.
And yes, it is absolutely normal. The first draft of any work is usually a mess. Revising and polishing it is not a danger sign, it's a healthy and necessary part of the process.