I'll take a humble stab at it:

Either management has reached a point in retiring aircraft that getting rid of more planes would mean losing profitable flying, and/or shareholders are beginning to raise their eyebrows.

Timing:

The recruitment effort has been building steam, and a new contract with favorable starting wages is needed to attract new talent. This comes at a time when our competitors are having to cancel a substantial amount of flights due to staffing issues. I think it is the perfect time for new CPAs to start to become more lucrative, and that we pilots might start to see some of the benefits of the pilot shortage at the regional level.

Terms of the offer:

As far as wages, the number I have heard is 3% which I don't think is enough to convince the pilot group to vote yes, so I'm optimistic that the number is higher. 401k would have to be better than the TA in order to earn a yes vote from the LXJT folks, so I'm thinking more than a 5% match. Since the letter from A and B said they wished to "keep it simple" I will assume that the work rules will be similar to what we have now. I am an optimist, and I'm excited to see what they have to offer. We need some good news to lift the pilot groups.

Hopefully this will get this thread back on track.