[Y-bar]

I propose two possible solutions:

A. Build some huge-ass rockets on the moon to accelerate it to offset any slowdown from changes in tidal energy.

B. Divert a few billion tonnes of asteroids to crash into the moon's aft, adding both to the moon's velocity and mass.

I believe that if we begin working on any of these solutions within a hundred thousand years or so from now we should be able to offset most of the projected long-term lengthening of the day.

[ben_w]

You'd have to put the rockets/target the asteroid impacts on the Earth, the effect on the Moon from this interaction is to push it into a higher orbit to conserve angular momentum of the combined Earth-Moon system.