Prior to Dec.. 12, 2003: When you submitted an open flying request, the “priority” you input was validated for accuracy, but not revalidated during the award process. In some cases, flight attendants were awarded trips they no longer desired.

Effective Dec. 12, 2003: When you submit an open flying request, the “priority” that you input will be validated for accuracy. If changes to your line of flying later disqualify you from using the priority you originally used to submit the request, the request will be rejected.
Items to Consider:

1. A definition of “priorities” is referenced in the September 1999 Contract Bulletin. Keep in mind that Priority 1 now includes making up time for declining a Section 8.J. or 12.I. reassignment and time lost due to trips dropped from vacation.

2. More than one open flying request may be input for the same trip using different priorities.

Storing Additional Trip Trade with Open Flying Requests (TTOF)

As the company works to comply with its commitment to increase flexibility through open flying trade allotments, allocations are changing more frequently than they have in the past. As the allocations are sometimes increased mid-month, it is appropriate to allow flight attendants to keep TTOF requests on file for days for which the allocation has been closed.

Prior to Dec.. 9, 2003: At the time TTOF requests are awarded, if your request was rejected due to “current allocations closed,” the request was also deleted from the system and was not considered in future TTOF processing. Additionally, you were not allowed to input a TTOF request if the trip trade allocations on the day of your trip were closed.

Effective Dec.. 9, 2003: If your TTOF request is rejected due to “current allocations closed,” the request will be kept on file for future TTOF consideration. You may enter a trade request for a trip on a day in which the TTOF allocation is closed. This trade request will be stored and again considered in the event allocations are increased.

Items to Consider:

1. If you no longer want your TTOF, please be sure to delete your request.

2. TTOF requests may be stored to a maximum of 63 requests each schedule month.

3. Due to a larger number of requests on file, it may take an additional 10-15 minutes to process TTOF at the larger domiciles.

Also:

You no longer need to enter a trade with open flying request multiple times if the allocations are currently closed for the day requested.  If your trade with open flying request is rejected due to “current allocations closed,” the request will be kept on file for future trade with open flying awards and will be considered when trades are again processed.

This comes from Onboard Service.  Here's the rest of the article:

You may have open flying requests rejected that were previously allowed to remain on file and potentially awarded. When you submit an open flying request, the “priority” that you input will be validated for accuracy. If your line of flying changes before open flying is processed and you are no longer eligible for the priority you input, the request will be rejected. For example, if you check priority #2 (guarantee below 70:00 hours), the open flying program will verify that yourguarantee is, in fact below 70:00 hours before allowing your request to be submitted. If your line of flying changes and you are no longer eligible for priority #2, your request will be rejected.