Check your PHP version on server. The only site that crashed for us after update (and I’ve updated ~20 sites) have php 5.4. Waiting for access to hosting panel right now to change it and test it, but if I would take a guess it would be it. So can anyone of you check php version on crashed sites and if changing to some 7ish will solve the issue?
Reversing to 5.7.10 helped for now on that one site for us.
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