I had thought there were four Navrathri every year, the two gupt ones then the two well-known ones in spring/fall. These are the ones I was observing as starting down devi-bhakti path.
However now finding out about Paush/Shakambhari Navrathri also, which is celebrated in many places in Dec/January. So for example, in this year it was celebrated first week January 2022.
So perhaps there are five Navrathri celebrated each year ?
Are there any others I still don’t know about ?
Shakambhari Devi is form of Shakti/Durga/Kali, had heard of the stories about her a few years ago but didn’t realize she had her own Navrathri too, which is wonderful btw :D