Agnus castus increases your progesterone levels, and this can sometimes mean that your oestrogen/progesterone levels are no longer evenly balanced; and in some cases, such as yourself, your cycle can indeed lengthen.
We would recommend that you now stop using Agnus castus as its done its job.
However, if you find that in time your issues re-occur, it can be taken again - in your case, for a few months only - to once more balance out your hormones.
Do you have questions? Please feel free to ask.
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