Twilio Studio flow rollback leaves execution state ambiguous

Direct Answer

Rolling back a Twilio Studio flow does not reset or clear variables for executions that are already running. An execution stays bound to the flow version that was published when it started, so a rollback changes the definition for new executions only. Flow-level variables keep their current values for the remainder of that in-flight run. If the interim version added a variable that the reverted version does not define, that variable remains available to the ongoing execution; the reverted flow definition does not strip execution-scoped state from runs that already hold it. Widget-level counters, timers, and similar markers also persist until the execution ends.

Confirmed vs Inferred Behavior

Item	Status	Notes
Execution binds to flow version at start	Confirmed	Studio ties each run to the published version active when execution begins.
New executions after rollback use reverted definition	Confirmed	Rollback republishes the older version; subsequent runs start from it.
In-flight flow variables retain values after rollback	Inferred	Variables live in execution context, but Twilio's public docs do not explicitly guarantee retention across rollback.
Interim-only variables persist in ongoing runs	Inferred	Reverted definition does not erase variables already set in that execution.
Widget counters and timers survive rollback	Inferred	Execution-level markers persist until the run ends.

Verification Steps for This Case

1. Start a test execution on the current flow version and note the Execution SID.
2. Set a flow variable and increment a widget counter inside that run.
3. Publish or roll back to the previous flow version.
4. Fetch the in-flight execution with the Studio REST API.

curl -u "$TWILIO_ACCOUNT_SID:$TWILIO_AUTH_TOKEN" \
  "https://studio.twilio.com/v2/Flows/$FLOW_SID/Executions/$EXECUTION_SID"

1. Inspect the execution context and confirm variables and counters still hold their pre-rollback values.
2. Compare Studio execution logs before and after rollback for the same Execution SID.
3. Start a new execution after rollback and confirm it does not expose interim-only variables absent from the reverted flow.

Missing Diagnostic Detail

Are you sharing state across executions through Twilio Functions, an external database, or another service? External state is not affected by Studio rollback and can become inconsistent if downstream logic depends on rolled-back flow variables. If yes, snapshot or migrate that state before rollback rather than relying on in-flight execution context.

Note: Because Twilio does not publish an explicit rollback state contract, verify this behavior in a non-production flow before applying it to production executions.