Last night I performed a switchover in the cluster.
Today I tried to catch an error when updating 14.19 ==> 14.23 on the old primary, but everything worked as expected.
The database started and connected to the replication slot on the new primary.
2026-06-17 14:16:08.367 [18915] @ // |6a305dc8.49e3|:8 (0): > LOG: received fast shutdown request
2026-06-17 14:16:08.368 [18915] @ // |6a305dc8.49e3|:9 (0): > LOG: aborting any active transactions
...
2026-06-17 14:16:18.318 [19845] @ // |6a305dc9.4d85|:462 (0): > LOG: restartpoint complete: wrote 1352773 buffers (32.3%); 0 WAL file(s) added, 14 removed, 14 recycled; write=661.408 s, sync=1.035 s, total=663.019 s; sync files=1196, longest=0.039 s, average=0.001 s; distance=3668114 kB, estimate=5645168 kB
2026-06-17 14:16:18.318 [19845] @ // |6a305dc9.4d85|:463 (0): > LOG: recovery restart point at C326/AA442CA8
2026-06-17 14:16:18.318 [19845] @ // |6a305dc9.4d85|:464 (0): > DETAIL: Last completed transaction was at log time 2026-06-17 14:16:08.367471+03.
2026-06-17 14:16:18.320 [19845] @ // |6a305dc9.4d85|:465 (0): > LOG: shutting down
2026-06-17 14:16:18.386 [18915] @ // |6a305dc8.49e3|:10 (0): > LOG: database system is shut down
...
2026-06-17 14:33:58.250 [24198] @ // |6a3285e1.5e86|:4 (0):1/0 > LOG: consistent recovery state reached at C329/102596D0
2026-06-17 14:33:58.250 [24198] @ // |6a3285e1.5e86|:5 (0):1/0 > LOG: invalid record length at C329/102596D0: wanted 24, got 0
2026-06-17 14:33:58.251 [24195] @ // |6a3285e0.5e83|:7 (0): > LOG: database system is ready to accept read-only connections
2026-06-17 14:33:58.260 [24437] @ // |6a328626.5f75|:1 (0): > LOG: started streaming WAL from primary at C329/10000000 on timeline 7