On the main crypto options venue there is an expiry every day. Each one removes a contract from the board and promotes the next one to the front. A trader who watches the implied volatility of the nearest contract will see it behave strangely around that moment. Most of the strangeness is bookkeeping.
A contract with hours left
An option with a few hours of life has very little time value. Its price is small, and a small change in that price converts into a large change in implied volatility. So the quoted volatility on the expiring contract is noisy. It can swing widely on trades that mean very little.
What it does measure is narrow. It is the market’s price for movement over the remaining hours and nothing beyond them. If something is scheduled inside that window, the number is high. If the window is empty, it can sink.
Before the expiry
In the last hours, the expiring strikes near the current price carry the most gamma. Dealer hedging around those strikes is at its strongest, which is the effect described in charm in a daily expiry market. When dealers are long that gamma, their hedging tends to hold price near the strike. The pinning argument is in max pain and the daily pin. Realized movement in those hours can be low for a mechanical reason.
After the expiry
The contract settles and is gone. The next day’s contract is now the front. It has a full day of life, a different set of open strikes and its own implied volatility. A chart of front-contract volatility shows a jump at that point. Nothing about the market’s view had to change for that jump to appear. The chart switched instruments.
The dealer map resets at the same moment, because the expired open interest no longer needs hedging. That rebuild is covered in the morning after expiry.
What stays comparable
A constant-maturity measure avoids the problem. A volatility index blends contracts to hold a fixed horizon, so it does not jump when one expiry rolls off. The crypto version is explained in DVOL, the crypto VIX. For a like-for-like view of volatility across days, that is the steadier reference. The front contract is a view of the next few hours only.
Where to see it
The NoVo Crypto Market Map shows dealer gamma by strike on the coins that have a real options book, and a volatility index reading beside it. Dr. NoVo, a markets SI, reads the two together and treats the hours around an expiry as a change in the book.