SkyTeam - Not a happy camper...

So DH and I are flying to Paris tonight :D:D.

DH is Silver Medallion on Delta and we each had enough miles to book roudtrip flights to Paris. Because the miles were coming from two different accounts, they had to book us on separate confirmations and couldn't link them beyond a small note in the record. All was well and good and we had both of our computers up at the same time so as to be able to sit next to one another on the 8+ hour flights. Perfect! It worked.

Fast forward to last night. We check in and we are no longer sitting next to each other. We were G&H so aisle and right next to that aisle seat. But seeing as my husband is Silver Medallion, the computer decided to sit him in an "Elite" middle seat closer to the front of the plane. Now we're both in middle seats and there are two seats that we would like, next to each other, but the Air France system locks all agents out (aparently) as soon as check-in begins.

How is a middle seat, no matter how close to the front of the plane (in the same class ticket) better than an aisle seat. AirFrance Computer FAIL!

So DH and I are flying to Paris tonight :D:D.

Fast forward to last night. We check in and we are no longer sitting next to each other. We were G&H so aisle and right next to that aisle seat. But seeing as my husband is Silver Medallion, the computer decided to sit him in an "Elite" middle seat closer to the front of the plane. Now we're both in middle seats and there are two seats that we would like, next to each other, but the Air France system locks all agents out (aparently) as soon as check-in begins.

How is a middle seat, no matter how close to the front of the plane (in the same class ticket) better than an aisle seat. AirFrance Computer FAIL!
I am sorry about your forced "separation" on the flight.
Middle seat is definitely inconvenient. There is a reason why middle seats are least wanted.
Despite Skyteam's claims that you can travel seamlessly across the alliance, you have discovered that it's not so. Last minute changes to your seat, happen on KLM, also owned by Air France. Your husband was moved to "supposedly" better seat, according to AF, but reverse happens too, when Diamond elites seated in Economy Comfort are moved to the back. Elites complaint that some airlines do not recognise their elite status. When they do, weird and unpleasant things happen.
Soo that you would know, all airlines transfer control of seating to the check-in process as soon as or before check-i begins. Your best bet is to get to the airport early and talk to the check-in agent. Take print outs of your itinerary showing that you and your husband were seated together.
If you are unable to secure seating together at the time of check-in ask an FA if they could help you in getting two seats together. There is no guarantee, but some FA's do try and help people in such situations. It's very difficult to find someone to accept a middle seat, but you never know, someone might be willing to give up a better seat and accept a middle seat with proper inducement that an FA could offer them.

On a future trip, let your husband pick a middle seat and you an aisle seat. If your husband was moved due to his Silver Medallion status, you would still retain your aisle seat.

I'm reading the OP as the OP and her husband selected their seats on DL.dumb. This is a recipe for disaster if flying on AF/KL, as the seat selections likely never made it over to the AF/KL system. (I currently have seats in business class on AF booked through DL on three trips, and only one of them propagated seat selections made on af.us over to DL.dumb. I think that's because the ticket was reissued by the SIN call centre. Right now, I've changed seats on one of those flights, and DL.dumb still has the old seat assignment.) Rule of thumb: Always select your seats with the operating carrier.

To AtlantaAlly, welcome to FT!

I guess I learned the lesson the hard way this time. Hopefully, we'll be able to make some changes when we get to SkyClub- or run over to the gate if necessary.

Thanks for the welcome :)

I'm reading the OP as the OP and her husband selected their seats on DL.dumb. This is a recipe for disaster if flying on AF/KL, as the seat selections likely never made it over to the AF/KL system. (I currently have seats in business class on AF booked through DL on three trips, and only one of them propagated seat selections made on af.us over to DL.dumb. I think that's because the ticket was reissued by the SIN call centre. Right now, I've changed seats on one of those flights, and DL.dumb still has the old seat assignment.) Rule of thumb: Always select your seats with the operating carrier.

To AtlantaAlly, welcome to FT!

Never happened to me in Business class. With AF/KL it makes little difference even if your seat selection is done by AF/KL agents. There are dozens and dozens of GM, PM and DM who had Economy assigned to them on KLM, who found themselves in the back at the time of check-in. happened to me twice in a row. Going from here to CPT was not a problem. But a couple of days before check-in at CPT. I lost my seat. I eventually did get my seats back both times. The third time, my seat selection remained intact. All these selections were made by calling KLM.

Never happened to me in Business class. With AF/KL it makes little difference even if your seat selection is done by AF/KL agents. There are dozens and dozens of GM, PM and DM who had Economy assigned to them on KLM, who found themselves in the back at the time of check-in. happened to me twice in a row. Going from here to CPT was not a problem. But a couple of days before check-in at CPT. I lost my seat. I eventually did get my seats back both times. The third time, my seat selection remained intact. All these selections were made by calling KLM.
Which KLM did you call? I'm sure you're aware that DL handles many/most of their calls in the US, so a call to "KLM" might not have actually had the seat selected in the KL systems.

I'm reading the OP as the OP and her husband selected their seats on DL.dumb. This is a recipe for disaster if flying on AF/KL, as the seat selections likely never made it over to the AF/KL system. (I currently have seats in business class on AF booked through DL on three trips, and only one of them propagated seat selections made on af.us over to DL.dumb. I think that's because the ticket was reissued by the SIN call centre. Right now, I've changed seats on one of those flights, and DL.dumb still has the old seat assignment.) Rule of thumb: Always select your seats with the operating carrier.

To AtlantaAlly, welcome to FT!

Couldn't agree more with this. There are whole threads devoted to this issue in the Flying Blue and Delta forums on how the system is messed up, especially when trying to select economy comfort seating.

I've had some success asking the medallion desk to select the seats I want and then wait a given amount of time to see if that seat selection has been propagated to KL/AF. If it does propagate to KL/AF, I don't have a problem unless there is an equipment swap/etc.

Which KLM did you call? I'm sure you're aware that DL handles many/most of their calls in the US, so a call to "KLM" might not have actually had the seat selected in the KL systems.
The seats I am talking about are those, assigned by KLM at the time of purchase on KLM's website. The problem was always on the inbound flight from CPT. Outbound seating remained intact every time for me, but others have reported losing outbound seats too. It's clear, it's not due to your perception that the seat assignment was not done by KLM
If you call after hours, your calls are handled by Delta, but during weekdays, calls are handled by dedicated KLM desk. It's a small department that sings its own tune. It's peddled as a KLM desk. It's the closest you can get to KLM in the U.S. I was also in touch with KLM in Amsterdam.
The problem of EC seats disappearing before OLCI begins is a common occurrence.