The out-of-office was on for two weeks, and now there's a number in a red circle that starts with a 1 and has a comma in it. The standard response (open oldest, grind forward) is how a good holiday gets amortized into a bad week. The backlog deserves a protocol, not a slog.
The two-hour protocol
Minute 0 to 15: delete the automated half. Sort or search by sender and bulk-archive every notification, newsletter, receipt, and digest. No reading. This typically halves the count and costs nothing: none of it was addressed to you personally.
Minute 15 to 45: the VIP and project scan. Search the senders who matter (manager, key clients, active deals) and read only those threads, newest first, because the newest message usually contains the resolution of the older ones. Extract what's genuinely yours into tasks.
Minute 45 to 60: ask the humans. Message two or three key colleagues: "Back today, what actually needs me this week?" Thirty seconds of their summary outperforms an hour of thread archaeology, and they know what died and what's alive.
Minute 60 to 90: targeted bankruptcy. Everything older than your last 48 hours away gets archived in bulk. Not deleted: archived and searchable. The rule that makes this safe: anything truly urgent from ten days ago has already re-sent itself, called, or escalated. Silence since is the answer.
Minute 90 to 120: process the recent tail normally. The last two days get the standard one-touch pass: answer, task, waiting-for, archive. You're current. Go get lunch.
How do you shrink the next one?
Before the next trip: an out-of-office that routes by topic ("invoices: Sam; the Harwell project: Priya"), so threads resolve around you instead of queueing on you. Filters on everything automated, built now, working forever; the Gmail setup covers it. And if Pidgy is watching the account while you're away, the return looks different in kind: arrivals already sorted, tasks already extracted, waiting-fors tracked, and a needs-you list a screen long instead of a number with a comma. The volume playbook handles the everyday version of the same math.