I have a couple of theories on the whole thing.
Theory 1
I think that the relationship between BMW/Sauber and LFS is an exchange, not of money, but of knowledge and capability. I think LFS have/will provide BMW/Sauber with a simulator that will meet their needs.
I think in return, BMW/Sauber have given/will probably continue to provide, telemetry data for LFS to derive physics. I think this is how the devs have come up with a patch they're extraordinarily confident about. They have real data to compare their computations with.
Net gain to LFS (all of us).. an F1. A real one. One that drives like a real F1 because all the data in it is real telemetry. It's my best guess, but I'm pretty confident.
Theory 2
I think the patch was planned for Sunday. I think at the beginning of the week, they predicted that they'd be finished before then, and that they'd have a day or two of relaxation before the nerves begin. Different nerves.. committing to a patch release is like stepping out on stage. It's a scary thing. A point, past which there is no return.
I think the patch ran wide, though, and at the end of the planned countdown they still had last-minute tweaks to do. Err on the side of caution. "better to waste a moment in life than life in a moment." Better to be sure than fall foul.
Another day is needed, and the LFS community is hungry (yeah, okay we're ravenous). What do the devs do? They can't release the patch because it's still not perfect (and we'd be bloody awful to deal with if it wasn't. We're like that. Look from outside in, to see.) Their big surprise. Their easter egg. The one they wanted us to FIND at Easter.. they had to fess up. WTF? (.html).
The patch may not be with us tomorrow either. I don't know. I just have a feeling that it's played out this way, out of anyone's hands. And if I'm right, then thumbs up to the devs. Whether the patch is here tomorrow, or we have to wait a few more days, I'll be grateful when it comes and I'm happier now, having thought a while on it, to wait as long as it takes.
Those are my theories