Backdated events via /api/v1/event/batch silently dropped beyond ~180 days — is there a cutoff?

Support
1

Hi all — I’m migrating ~30 sites from Plausible to Pirsch this week. Pageview import via your Plausible importer works great. For custom events, I’m using /api/v1/event/batch with the time field per Marvin’s reply in topic 150.

I’ve hit a wall and I can’t find documented anywhere: events with time older than ~180–200 days return HTTP 200 but never appear in stats. Within that window they land correctly at the historical date.

Results (single backdated event per probe, disable_bot_filter: true, residential-looking IPs, varied UAs):

time value Days back Landed
2026-04-29 1 :white_check_mark:
2026-04-27 3 :white_check_mark:
2026-04-23 7 :white_check_mark:
2026-03-31 30 :white_check_mark:
2026-01-30 90 :white_check_mark:
2025-12-31 120 :white_check_mark:
2025-12-01 150 :white_check_mark:
2025-11-01 180 :white_check_mark:
2025-10-12 200 :cross_mark: silently dropped
2025-09-22 220 :cross_mark: silently dropped
2025-04-30 365 :cross_mark: silently dropped

Same pattern was observed on /api/v1/hit/batch.

Things I’ve already verified to rule out misconfiguration:

  • Same auth, same identification_code, same payload shape — only time changes between probes that work and probes that don’t.

  • Live event ingestion (no time field) on the same domain works correctly and shows up immediately in stats.

  • Within-window backfilled events match the source data closely (visitor counts within a few % of the original Plausible CSV after deduping by synthetic IP/UA fingerprints).

  • identification_code is required and is the correct field name (the docs only show it explicitly in the single event endpoint section, not the batch section, but it’s needed in both).

  • Bot filter is bypassed (disable_bot_filter: true) and IPs are from residential ranges, not datacenter.

I understand from topic 66 that 200-on-drop is intentional for bot filtering. Does the same apply to backdated entries past some threshold? If so:

  1. Is the cutoff really ~180 days, and is it a hard line or sliding?

  2. Is it tied to plan tier, account age, or fixed for everyone?

  3. Is there a way to backfill events further back? My oldest sites have 1+ years of Plausible event history I’d hate to lose.

Thank you!

2

Hi Steven,

Thanks for the detailed report :slight_smile:

When was your dashboard created? We might need to manually change the creation date, or otherwise the “imported” statistics won’t show up on the dashboard. I would assume that it was created in October, so the data might be there, but isn’t visible?

What’s the domain for the dashboard? You can share it privately via support@pirsch.io if you like.