@arslan I don’t see anybody working on this, so your only choice is to disable Memcached.
SG head of tech has confirmed to me their platform is not to blame and they’re rather awaiting a “fix” from ACF, whatever this means.
I’m pretty sure at least the root cause could be identified by a single day debugging session, but who’s going to undertake it? I don’t have skilled enough resource available to do this for a while. ACF team seems to be staying mostly quiet here, too. Anybody else?