Google removed the 50-conversion figure from its Smart Bidding learning period guidance

The help page on learning period duration used to say calibration could take up to 50 conversion events or three conversion cycles. It now says only that it typically takes one to two conversion cycles, and can be faster with more conversion data. The 50-conversion rule of thumb many advertisers cite no longer has a source in Google's documentation.

Spotted by Hana Kobzová on LinkedIn.