OK... I have been waiting for some of the other gals to chime in... I don't do long distance rides as a goal, so I can't really offer advice.
Though I can make some generic suggestions for you, tygab
In terms of rest - don't stay off the bike completely - do what is called "active recovery"... that is, ride, but at a lower heart-rate or speed or power output - however you measure your ride.
(You don't need a piece of machinery like a heart rate monitor to do this is you haven't got one... you know when you push your body hard and when you don't. Active recovery should feel like a comfortable ride with your heart rate elevated just a little... not the thumping that happens when exerting yourself intensely.)
So your next question - "when do I resume?" - is actually, "when do I start increasing my intensity again?"
And that depends. What are your goals? What are you training for?
Another enduro/long distance ride? Then I am guessing you should be riding those distances, though not at race pace, interspersed with shorter rides (Metric riders... help me out here please?)
If your goal is shorter races - 20 km or 40km (12-25 miles) then do some intense rides at this distance (to build your anaerobic threshold). Include some intervals to improve aspects of racing like sprints. But also do some longer rides at a lower/recovery rate to build your aerobic base.
Remember to rest well after rides... I have 1-2 rest days a week, and after an intense ride (like yesterdays race) I will do a slower longer ride to help disperse the toxins that can build up in a race and ease the muscles (thats what I will do today). Tomorrow is a rest day - no ride at all. I will ride Tues, Wed and Thurs and on Friday I will have no ride at all in preparation for my Saturday race.
Only you can decide your goals... if you like riding the longer distances, then some of those long events might be your goal...
Good luck, and hopefully someone else will chip in soon with some long distance suggestions