You can over-ride and it can be that century ride that is at the back of your mind. You HAVE to get out and ride to get fit enough for that one ride.

You don't.

With the mileage and training you have behind you you could easily swap a few training rides for "Smell the roses" jaunts. You could even go down the gym for a few weeks to give a change from your routine.

Earlier this year I did a 100 miler at night. The night bit was fun but I had just had a winter recovering from a knee problem and the weather definitely cut short any training I might have done. Cut a story short but I managed the ride and 70 miles at dawn I finished the ride at Brighton--And still had to do the other 30 home to do the Century. A route I usually did once a month with a break for coffee but there was no way I was going to stop. If I had- it would have been for a call for the sag wagon. (My Wife)

Seeing as how you are a "Recent" retiree like me- I know how the riding has become a compunction. You have to do it and my rides are infrequent now. Still get in around 100 miles a week- but I was hoping for 150. Too many jobs to do around the house and the garden.

So I suggest a break from training but still do a few rides- get down the gym- or turn over the veggie patch to find muscles you haven't used for years. Keep active and keep the fitness up till you feel ready to do that training metric at 20mph.