Anyone seeing excessive latency in Zapier hook/refresh cycles?

Summary
Zapier-based channel comms are very latent.

Steps to reproduce
Set up Google Sheets. Set up OAuth Zapier hook to send an update to a channel. Update Sheet. Check for arrival time of channel update.

Expected behavior
I expect this to appear within seconds.

Observed behavior
There are no error messages in app.
I do see occasional {“level”:“debug”,“ts”:1618863597.5224683,“caller”:“app/web_conn.go:443”,“msg”:“websocket.read: closing websocket”,“user_id”:“4m7nja9j67ghtgujuyj485fg5e”,“error”:“websocket: close 1006 (abnormal closure): unexpected EOF”}
but these pre-dated Zapier integration.
I see a one-to-one correlation between Sheet updates, Zapier hooks, and log-based HTTP 201 acknowledgements. So that looks ok. But gawdawful latency (like a minute or three. madness…)