This is probably common sense to all the readers here, but you should likely not add a noindex and remove the noindex on specific URLs often or heck, even infrequently. It will confuse Google, slow Google down in terms of seeing if that page should be indexed again in the future and will result in that page not always doing well in search.
John Mueller from Google posted on Twitter that when products go out of stock and back in stock, you can use the noindex. But he said not to do it too frequently where you are flipping the status between index and noindex on a specific URL. He said try to be consistent with Google, which is advice he has given time and time again.
John said "I generally don't see a problem with using noindex for pages you don't want indexed, I'd aim to be consistent and not flip states for individual URLs too frequently."
Here are the tweets:
I generally don't see a problem with using noindex for pages you don't want indexed, I'd aim to be consistent and not flip states for individual URLs too frequently.
— 🍌 John 🍌 (@JohnMu) January 24, 2019
I wouldn't noindex a page that you know you want Google to index again in the near future.
Forum discussion at Twitter.
