I’m having the same issue. After 10 months of successfully having Post Notifications sent promptly after a new post goes live every Monday, today’s post did not get emailed to anyone despite a new post going live.
I’ve confirmed via the Reports that no email was sent out today, so it’s not a SPAM issue on the receiving end. It’s not being generated nor sent.
The post went live maybe 4 hours ago, which seems a bit long for emails to not be sent even as background jobs.
And as antya63 noted, the update did this for me too.
The ‘/ issue comes up in other areas too, for example in a form, if you have “there’s” it shows “there’/s”.