This may sound surprising, but I have observed this switch in me. Whether it is just mentally deciding that the pressure of work will not get to me, or whether it is the decision to step out of a dark energy field. It is absolutely possible to make this decision and see it through instantaneously.
In the olden days I always gave myself 28 days to step out of an energy field for the reason that even with the best conscious intentions it takes a while to bring the sub-conscience along. You can literally monitor how the "system" is dragged along a conscious choice in a new direction. In the first days the "system" rebels and you feel horrible; the first couple of weeks are also heavy lifting, whereas in weeks three and four it does get progressively easier until the new routine becomes the new normal. Twenty-eight days, as in four times a completed cycle of seven days. However, last time around when I thought about starting a new cleansing process, I saw countless sevens popping up from all directions. It was as if the WAY wanted to communicate, "change your intentions and you are instantaneously healed brother".
Some appeal to a higher authority with prayers, some like me find meaning in the symbols of the WAY, but whatever spiritual path we travel, the switch to step towards the light today is always at our disposal. Let's make the switch today.