Date & is within a protected time period

What causes this issue?

You see this message in one of the following processing situations:
You are processing a change master record:
Entering the valid-from date
Entering an alternative date
Date shift of valid-from date or alternative date
Assigning alternative date to change object or deleting an allocation
You are processing a change object with reference to a change number
whose valid-from date is in the
<DS:GLOS.3526BEDCAFAB52B9E10000009B38F974>protected time period</>:
Changing a change object (for example, BOM or routing)
Assigning or changing a revision level

System Response

The system checks the control data for data shifts in Customizing for
engineering change management. In your company, a protected time period
is defined.
In the fields <LS>Warn. time in days</> and/or <LS>Error time in days
</>, a number of calendar days defines how the protected time period is
calculated.

How to fix this error?

If the message is:
A warning message, processing is allowed. However, we advise you to
check the change objects. If you confirm the warning message, you can
continue processing.
An error message, processing is <ZH>not</> allowed.

Error message extract from SAP system. Copyright SAP SE.