clarifications

Author: carbolymer

cardano-rpc/docs/node-kernel-access/prereqs-implementation-details.md

@@ -117,7 +117,7 @@ case fromConsensusQueryResult qim consensusQuery raw of
 ```
 
 With the snapshot-based design, all queries within one `nkaWithSnapshot` call share the same `ReadOnlyForker`, so era mismatches between queries inside a single snapshot are impossible.
-An era mismatch can still occur if the node transitions between the era determination (outside the snapshot) and the snapshot acquisition, but this is an extremely rare race at hard fork boundaries.
+The only cross-snapshot era race is in `Submit.hs` (see 4.8): era detection uses one `nkaWithSnapshot` call, then `nkaSubmitTx` is a separate call - an era transition between them is theoretically possible at hard fork boundaries but extremely rare.
 Throwing is acceptable since the client can retry.
 
 ### 4.10 `QueryCurrentEra` routes through `toConsensusQuery` (verified)