Error Overview
When trying to deploy a Flow that was built on a org on the Spring '26 release of Salesforce that includes a FlowSchedule, to an org that has not yet been upgraded to the Spring '26 release of Salesforce, the error Error parsing file: Element {http://soap.sforce.com/2006/04/metadata}dayOfMonthToRun invalid at this location in type FlowSchedule is received during deployment validation.
When selecting a version of the metadata API below Version 66 during a comparison, the fields of <dayOfMonthToRun> and <frequencyNumber> are surfaced even though they are not supported.
These fields are only supported on orgs that are on the Spring '26 version of Salesforce.
More information on those fields can be found here
These fields look like this in your Flow in a comparison
<schedule>
<dayOfMonthToRun>0</dayOfMonthToRun>
<frequency>Weekly</frequency>
<frequencyNumber>0</frequencyNumber>
<startDate>2026-02-01</startDate>
<startTime>01:00:00.000Z</startTime>
</schedule>
Resolution
To work around this issue and deploy your Flow to an org that has not yet been updated to the Spring '26 version of Salesforce the following steps need to be followed:
Download the deployment package from the failed validation.
Unzip that package
Open the .flow file from in the Flow folder that matches the name of the flow you are getting the validation error on
Manually edited the file to remove the two lines of code for those fields
They will look like:
<dayOfMonthToRun>0</dayOfMonthToRun>
<frequencyNumber>0</frequencyNumber>
Save the file
Zip the deployment package back up.
Using a
Compare and Deploy, select theLocal Filesoption as the source.Select your newly created zip deployment package
Select the org you want to deploy too as the target.
Validate and deploy
Once the rollout of the Spring '26 Version of Salesforce is complete, this should no longer be an issue