In high-frequency energy trading, it's possible for a trader to have hundreds of orders in the book, possibly on more than one exchange, e.g. ICE and NYMEX.
A trader may be running dozens of algorithms simultaneously. Each of these may respond independently to the changes it detects in the market data, as well as to the timing and fill data from its own execution reports.
In some situations, a sudden price change in an influential futures market may require the modification of order prices on both sides of the market over dozens of delivery periods. And then of course there are spreads, butterflies and other futures strategies that link the prices of their legs. Orders in these instruments may also have to be adjusted.
It's important to realize that even within an exchange, instruments related in the economic sense are not necessarily traded on the same match engine, and that execution reports (to individual traders) travel along different paths than market data (published generically to all subscribers). A multi-product strategy must take this into account. NYMEX and ICE also trade financially-settled equivalents to each other's physically settled contracts, and these take time to change as well.
Algorithms vary in terms of how much data they require in order to detect and act on a price change. The algorithm operators can also run them differently on days when the market is expected to be volatile, e.g. with thresholds that reduce the risk of a misplaced execution.
Even a trader with black boxes co-located at the exchanges still needs time to transmit the necessary cancel/replace messages, especially since other traders will be attempting to do the same thing. A mispricing in a set of linked markets can therefore exist for several milliseconds, and in some cases as much as several hundred milliseconds, i.e. the time needed for the majority of algorithmic participants to update their local book states and begin waiting for the next triggering event.