Decay method during vacation

How do you set the decay method when you aren’t training for a while? I’m going on vacation in four weeks and won’t be training on the bike for about 18–20 days. Right now, I have it set to “Optimal.” Would it make more sense to switch it to “Small” or “None” during the vacation?

Small Decay can be used to limit signature decline during your three weeks off.

No Decay is useful when you are actively training but not exhibiting maximal efforts frequently. Signature adjustments will reflect changes in TL.
For example, you’ve established a viable signature with a recent BT and expect you’ll be mostly riding endurance for a while (extended base phase).

Optimal Decay would more likely result in a BT when you resume training once you insert some maximal efforts on HIT days (sprints or intervals to failure).

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