Odd and even weeks over a year

[pyrog]

A rule like week 02-53/2 Sa 09:00-12:00 work fine for year 2020 😃
but not for year 2021 😢

day	week	state
2020-12-19	51	closed
2020-12-26	52	opened
2021-01-02	53	closed
2021-01-09	2	closed
2021-01-16	3	opened

Is there a syntax to described "every to weeks" ?
Or is it an issue and the grammar should be expanded ?

PS: This example work fine but only for some time 😞

2020 week 02-53/2 Sa 09:00-12:00;
2021 week 01-53/2 Sa 09:00-12:00

[ypid]

Without looking deeper into this, I think you found a limitation of the current syntax. I guess I also did not think nor test this before. So I would propose to discuss this on the tagging mailing list or on the wiki talk page.

[Bibi56]

@pyrog, you're missing the week 1: after 53 it's 1.

The first week of the year is the first week of January containing a Thursday or the 4st of January (it's the same).