Hi!
It seems that CFbot was still unhappy with pg_upgrade test due to epoch removal from NextXid in controldata.
I've reverted this change as support for "epochless" 64-bit control data with xids that haven't yet switched to 64-bit would otherwise need extra temporary code to support.
I suppose this should be committed with the main 64xid (0006) patch later.
PFA v28 patch.
Thanks, you all for your attention, interest, and help with this patch!
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