There are always websites trying to trash or change history. I don't think there is any doubt it was non stop. Where and how would a stop have been engineered? There was nowhere in between they could feasibly have gone without being seen, and why would they do that? It was a prestige national project and you just don't cheat on those. It was a pretty heroic effort.
Read about it chapter and verse first-hand by Boris Chertok who was closely involved in building and modifying the aircraft - in his extraordinary book "Rockets and People" available as a free download from the NASA library (Vol 1 for this story).