CBS Sports is reporting the NFL and the NFL Referees Association have reached an agreement regarding backup crews as of Wednesday morning.

The owners, who previously haven't shown any willingness to give on the referees' benefits issues that led to the lockout, have become more involved in the talks.

The 21 backup officials won't become members of the NFLRA, but will enter a developmental program to be trained to work NFL games. They will work with NFL crews throughout the week but won't work games and won't be eligible to be subbed out.

Talks extended into the early morning hours on Wednesday, and are expected to continue.

The sides haven't yet resolved the issue of referee retirement plans, but an NFLRA source told NFL.com that the officials moved a bit off their position Tuesday.

Owners had sought for all officials to go to a 401(k), and the NFLRA offered to have new officials on such a plan, with existing members grandfathered in under the old pension.