I have a scenario, where closed cases (opened by customers through email reply) can not re-open after 2 weeks.

I am managing everything via Flows (before create/update). Is it possible to send an email alert to the customer, that his case couldn't be re-opened, and he needs to send a new email ?

When using the 'Before Create/update' visual flow, there is no option to send email alerts, I assume cause of DML restrictions.

I have a scenario, where closed cases (opened by customers through email reply) can not re-open after 2 weeks.

I am managing everything via Flows (before create/update). Is it possible to send an email alert to the customer, that his case couldn't be re-opened, and he needs to send a new email ?

When using the 'Before Create/update' visual flow, there is no option to send email alerts, I assume cause of DML restrictions.

With @cropredy suggestion, here's what I get:

New field on case: Late_Reopen_attempt__c

Flow: Case Before Create/Update:

**** The main problem with this scenario, is that the data is saved to the case record. This is something I want to avoid.

So, I added a validation rule on the case:

But I get to a race condition, where I don't want any updates, but only to switch the Checkbox indicator.