Recurring events: weekly events set one day early after 30 October

Hi, I have been using your plugin on several websites for a couple of years, and love the customisation I can have.

I currently have an error where when I create a weekly recurring event, it works fine up until 30th October, but thereafter it it puts in the event a day early- as if the code has only 30 days for Oct rather than 31.

For example, we have set a recurring event (“test event”) for Thursdays every weeks and the events generated are: 4 Oct, 11 Oct, 18 Oct 25 Oct (correct) but then instead of 1 Nov,8 Nov, it goes to 31 Oct, 7 Nov 14 Nov etc although these days are Wednesdays.

I have had this problem since the new release that come in just before 25th May (GDPR day)

I would appreciate any help!

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