Clocks: when each tool's data is live

Monday 2 November 2026, 20:40 in Hanoi, 08:40 in New York. You open your desk for the pre-market read. ATAS X shows NQ at 28,814.00. Your option screen shows a level and a gamma reading that look fresh, but they were computed on Friday 30 October at 16:15 ET, when NQ traded at 28,556.50. Since then NQ has moved 257.50 points, and the option numbers are 64 hours old. Nothing on the screen is broken. Each tool is simply on its own clock. This lesson teaches you to read the clock before you read the number.

Key terms

Time stamp (mốc thời gian): the moment a number was computed, not the moment you look at it Definition. Every number on the desk has one.

Live (trực tiếp): the source is open and the number was computed within the last few minutes Definition. Our desk’s Vexity client calls option data live when it is at most 3 minutes old.

Frozen (đóng băng): the source’s session is closed, so you see its last snapshot Definition. A frozen number was right at its stamp and is out of date now. This is normal, not a fault.

Stale (cũ, chậm): the source should be live but is not: the feed is behind, the producer stopped, or it is a holiday Definition. Stale is an alarm. A number with no time stamp counts as stale.

Snapshot (ảnh chụp dữ liệu): a copy of a set of numbers at one moment Definition. Option levels are computed from a snapshot of the option chain (the list of all strikes and expiries, OPF1.04).

Terms you need: option chain, open interest, implied volatility and gamma. An option chain (chuỗi quyền chọn) lists every available strike price and expiry date for an underlying index or future (OPF1.04). Open interest (số hợp đồng mở) is the count of option contracts still open at the clearinghouse after yesterday’s settlement Definition. Implied volatility (độ biến động hàm ý) is the annualised move size priced into option premiums (OPF4.03), and gamma (gamma) measures how fast an option’s delta changes as price moves (OPF3.02).

Chart first: one day, two clocks

How it works

Four clocks on one desk

PLAT1.01 split the desk into tools. Each tool is live at different times Definition:

In US daylight time (mid-March to early November) subtract one hour from every ICT time: the option band runs 20:30–03:15 ICT.

Why 16:15 and not 16:00? The index and index-ETF options trade 15 minutes after the stock market closes, so their data keeps moving until then Definition. Then the vendor stops computing and serves the last snapshot until the next cash open.

Two details catch new traders. First, the first live option frame can arrive a few minutes after 09:30; our client keeps the “frozen” label until it does. Second, open interest (số hợp đồng mở, the count of open option contracts) is published once a day, before the session Definition. So even a live chain carries yesterday’s open interest. OPF1.06 maps which fields are observed, delayed or modelled.

Frozen is never current

A frozen level is a fact about 16:15 ET yesterday. NQ keeps trading for 16¼ of the next 17¼ hours (all but the halt), so by your pre-market read the distance between price and that level has changed Definition. The rule on this desk: frozen is never current House rule. You may use a frozen number as yesterday’s map, labelled with its stamp. You never write it in your plan as “now”.

Holidays and early closes

On a US market holiday the futures may trade a short session while no option session opens. The clock says “cash hours” but nothing goes live, so the data is stale, not frozen Definition. On early-close days, such as Friday 27 November 2026, the option window ends early. Check the CME and Cboe holiday calendars at the start of each month.

What the data says

How far does NQ travel while option data sleeps? Our lab measured it.

Worked example: the Monday read

Back to the hook, step by step.

1. Read the clocks. 08:40 ET Monday 2 November is 20:40 ICT. US clocks changed on 1 November, so Vietnam is ET + 12.
2. Read the stamps. ATAS X: last NQ trade a second ago, live. Index option data: stamped Friday 30 October, 16:14:59 ET, frozen, 64 hours 25 minutes old. Your brief: not written yet.
3. Measure the drift. NQ at the freeze: 28,556.50. NQ now: 28,814.00. Drift: +257.50 points, in the top quarter of our 58 mornings.
4. Write it honestly. A level that sat 200 points above price on Friday now sits 57.50 points below price. Your plan says: “Friday 16:15 ET snapshot, level X; NQ has since moved +257.50. Re-check at the first live frame after 09:30 ET (21:30 ICT).”

The mirror. Friday 30 October, 08:40 ET: the snapshot was from Thursday 16:15 ET, NQ 29,182.50. NQ now traded 28,804.75, down 377.75 points. A level that was 300 points below price on Thursday is now about 78 points above it. Up or down, the frozen number keeps its price; your position relative to it changes.

The failure case. Two kinds of failure:

• Close by luck. On Thursday 3 September NQ at 08:40 ET was only 6 points from the previous freeze. A frozen level looked current. It was still a Wednesday number: open interest and implied volatility could have changed by the open. Close is not current.
• Cash hours, nothing live. Monday 7 September 2026 was Labor Day. NQ futures traded until 13:00 ET, so at 10:00 ET ATAS X was live, but no option session opened. The last option snapshot was Friday 4 September, 16:15 ET. A trader who saw “10:00 ET, inside the window” and trusted the screen read data 66 hours old.

Common mistake: treating “the screen updated” as “the number is live”. Screens redraw on every futures tick, while the option levels under them can be frozen. Read the stamp, not the motion.

Common mistake: reading the median drift as a forecast. “NQ usually moves about 174 points overnight” is a base rate of distance, not a direction and not an edge. It only tells you how wrong a frozen number is likely to be.

Do it on the platform

Prop-firm note: a funded account’s trading day ends at a time the firm sets, earlier than CME’s 17:00 ET halt. That time is a firm rule, shown as a dated rule card in PLAT2.08 and PROP2.01.

Drill: stamp your screens

At your next pre-market read:

1. Write the time in ET and ICT.
2. For each screen (ATAS X, TopstepX, option data, your brief), write its last time stamp and label it live, frozen or stale.
3. Find NQ’s last trade before 16:15 ET yesterday on ATAS X. Write the drift to now in points, and compare it with our median of 174.

Recap

• Each tool has its own clock: futures nearly all day, index option data 09:30–16:15 ET on cash days, the brief never.
• Label every number live, frozen or stale from its stamp; no stamp means stale.
• Frozen is never current. In our lab’s 58 mornings, NQ was a median 174 points from the freeze by 08:40 ET.
• From Vietnam, every pre-market read falls in frozen option time; the first live frame comes after 21:30 ICT in winter.

Further reading

• CME Group, trading hours for equity index futures: https://www.cmegroup.com/trading-hours.html
• CME Group, holiday calendar: https://www.cmegroup.com/tools-information/holiday-calendar.html
• Cboe, SPX options specifications (trading hours): https://www.cboe.com/tradable_products/sp_500/spx_options/specifications/
• OCC, volume and open interest reports: https://www.theocc.com/market-data/market-data-reports/volume-and-open-interest
• Our lab: across 58 NQ mornings (August to November 2026), NQ was a median 174 points from its 16:15 ET price by 08:40 ET the next day.

Prerequisites: M0.04 Trading sessions, PLAT1.01 The desk map · Next: PLAT1.03 Without the suite or Vexity, which maps each desk number to a stock-ATAS or free source with its own clock · Goes deeper: PLAT5.02 (Vexity’s freshness fields), MKT1.04 (holidays and the US clock change)

Educational content only, not financial advice. Futures trading involves substantial risk of loss. Examples use real historical NQ prints for illustration; they are not trade calls.