I'm a 1K and I get several of them a year on International flights.
For some reason I very rarely get one on a Domestic U.S. route (probably a combination of fewer 3-Class aircraft in the domestic market and also perhaps they don't overbook Economy as much Domestically as Internationally).

You can never count on them, but if you are savvy enough on the routes you take and the average loads, you can use a small bit of strategy to increase your chances (booking flights that you know from experience have light Business loads yet historically overbooked in Economy).

In the absence of such first-hand knowledge or ability to obtain it from a friendly agent or fellow frequent flyer, I would offer these tips for International Economy to Business Operational Upgrades:

First, there are 3 types of Operational Upgrades:

1. Advance Operational Upgrades. This is when they evaluate the load a few hours in advance of the flight and make immediate Operational Upgrades up to a certain point in order to not have to do them all at the last minute at the gate, and therefore face possible delays and gate chaos as they play musical chairs. This also allows them to free up your Economy seat in advance and have it ready for assignment when other passengers check in.

If you've been given one, when you check-in, you will find you have already been upgraded Operationally.

2. Gate Operational Upgrade. This is a more or less last minute version of the above, or a final continuation of the above, often releasing any holds that were hanging in there for last minute full fare Business passengers, or possible reaccommodations from canceled/delayed flights.

Usually you are paged over the Public Address System to approach the podium and see the agent. There you are given your Operational.

3. On-board Operational Upgrade Very rare. These are usually done if say someone never showed up for their Business seat, and they still have pax waiting for Economy. They may come on board and move you up. But because this type of thing is done at the last moment, some gate agents just put one of those waiting passengers in Business because it's quicker and they can get the plane off in time.

Knowing the above, here's some advise:

- Don't check in too early. Reason? If you've already checked-in before they start doing Advance Operational Upgrades you may get skipped over because you're already holding your Economy Boarding Pass and they don't want or can't track you down. No sooner than 2 Hours should be fine and most Advance Operational Upgrades have been done (if any) by that time. If you are checking in for a connecting International flight in another city, if you haven't already been given an Advance Operational Upgrade, ask them not to check you in for the International segment yet. Tell them you'll do that at the next airport (this may mean reclaiming luggage at the connecting point and rechecking it, if you should have some). Then when you finally arrive at your connecting airport where you depart to your International destination, check-in and hope you got an Advance Operational Upgrade assigned while you were in the air.

- "The Speech" If you didn't get an Advance Operational Upgrade when you checked-in, there is still hope for a Gate Operational Upgrade. You can just sit and hope they call your name, or you might improve your chances by giving "The Speech." Wait until the gate agents are not busy or helping other passengers, try to identify who the head or senior Gate Agent is, walk up, smile and greet them placing your Economy boarding pass on the counter and say something like:

quote:
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Hi. I'm Mark Love. I'm traveling with you in Economy today [insert mention of Full Fare if applicable] and I've got a nice aisle seat which I'm very happy with. But if at any time, you should need my seat for any reason, I'd be more than happy if you wanted to move me up. I'll be sitting right over there. I've got an easy name to remember...Love. Thanks!
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No need to flaunt your status and accidentally give a bad impression of entitlement. They can see your status for themselves on the Boarding Pass you placed in front of them.
Even if they say no, it's checked-in full, say "Well Thanks anyway. Please feel free to call on me if anything changes." Sometimes folks who have checked in for their Business seats in another city miss their connections or are late and those seats could free up at the last minute. Many times I've been told no and to take my Economy seat, only to hear my name being called a short time later!

Other Things:

- If you are hoping for a Gate Operational Upgrade stick around the gate area. Don't go off shopping or to the Red Carpet Club. If you don't answer a page, they may move to the next person on the list.

- If you must visit the Red Carpet Club, ask the Club receptionist to note your current location in your record. There have been instances where Gate Agents call the Club to have you paged.

- Traveling solos have a better chance of Operational Upgrades. Not having 2 or more seats available next to each other may deter an agent from upgrading you and they may look for solos.

- I've heard that ordering a Special Meal can reduce your chances as well, as they may not want to have to mess with getting you the Business Class version of your Special Meal.

- Dress nice. When giving "The Speech" you are basically doing a sales job. They are more likely to upgrade you if we don't look like the slobs we all know we are.

- And does it really need to be said? Your Premier Status and Fare Paid will have an impact on just who gets bumped up.

Using the above, I've been very lucky over the years. Especially with Advance Operational Upgrades by attempting to book a flight that traditionally is oversold in Economy but not quite in Business.

Still, it's always a crap shoot. But if you don't want or can't upgrade in advance using qualifying certs or miles, it's better than doing nothing, IMHO.

[Edited to add]

Update:One thing that may have effected Advance Operational Upgrades and The Speech to some degree recently, is the offering and hard-selling of same-day at-airport upgrades for $$$ at some locations.

But if they don't sell enough of those and they still need Economy seats, they have to do Gate Operational Upgrades still at some point, and anything you can do (in a positive non-entitlement way) to make the agents aware of your willingness and attractive-ness to be Operationally Upgraded, goes in your favor and gives you an edge, IMHO.

If after they've offered to sell you the upgrade and you decline, you can amend The Speech to say,

quote:
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Well, if you don't sell enough and you still need to do Operationals in the end, please keep me in mind. Thank You.
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...that may still help you out (and I'm sure worked for me recently out of LHR).