Calendar hygiene for discretionary scalpers: advanced edge cases

[LondonScalper]

The basics of calendar hygiene are easy to state: know the times, be flat for the big ones, don't trade what you don't understand. The edge cases are where my process kept breaking, so here are the ones I've had to write specific rules for.

Clock changes. For about two weeks in March and one week in late October/early November, the US and UK are on different daylight saving schedules. A US release that normally lands at 13:30 London comes at 12:30 instead. I've been caught by this twice in twenty years, both times because I trusted memory over the calendar.

Releases that move but aren't marked as important. Calendars rank events by expected impact, but sometimes a low-ranked release becomes the focus of the day because of what's going on in the market. When inflation is the main story, even a regional price survey can move the euro.

Back-to-back releases. When three medium releases come in a 45-minute window, the combined effect can be bigger than one big release, and the spread tends to stay wide across the whole period rather than recovering between them.

Data leaks and early releases. Rare, but when a number appears seconds early on some feeds, the first move happens before "release time". I no longer enter anything between one minute before and five minutes after a scheduled release, whatever the chart says.

[Shadow Trader]

The clock change one is due again soon, so this is well timed. The UK goes back on 25 October and the US a week later, and for that week the 13:30 US releases land at 12:30 London. I put a note on the desk calendar for the whole week rather than trusting the time zone setting on the economic calendar.

I'd add one edge case to your list: holidays in one country only. On a US holiday the London afternoon gets very thin, and spreads after 15:00 can sit wider than normal with nothing at all on the calendar.

The back-to-back point matches what I've seen. When three medium prints land inside 45 minutes, I treat the whole block as one tier-one event and stay flat from the first until five minutes after the last.

Your one minute before, five after rule is close to mine. How did you settle on five minutes after? I've wondered whether three is enough for medium releases.

[Shadow Trader]

I settled on five minutes after for a boring reason. Three was enough on quiet medium prints, but on the ones that matter the second spike often lands between minute three and five, and that is when I used to click thinking it was over.

So five is the floor for any single medium release. For a back to back block I still stay flat until five after the last print, not five after the first.

The low ranked release that becomes the story of the day is the harder edge case. When CPI or labour is the week's theme I treat any price survey in that currency as tier one for flat purposes, even if the calendar paints it yellow.

Desk calendar for the DST week stays. Phone calendar apps have shifted a release on me before, so the paper note is the one I trust for that week only.

LondonScalper, on the early leak rule, do you flatten open runners one minute before as well, or only block new entries? I close runners too, because a stop sitting through a leak is still a news trade.