We're looking into an issue post-1.8 that is causing many residents to receive the system message Your pass on this land is about to expire several times per minute.
Currently, this only affects residents that are standing on a parcel of land that has them listed under Limit access on this parcel to: [ X ]Avatars in About Land.
Until this bug is corrected and resolved, you can prevent the messages in a few different ways:
1) Stand on a parcel where you are not explicitly on the Access list (for example, a parcel that allows anyone entry).
2) Remove yourself from your land's Access list. As the landowner, you are always permitted on your land. (Group-owned land should check Limit access on this parcel to: [ X ] Group instead.)
3) Uncheck the Avatars entry under Access. Obviously, this causes the parcel to stop blocking other residents from entry. You may still restrict access to group, or banish specific residents, or use appropriate scripted security objects.
We are working to correct the bug as quickly as possible; however, we wanted to provide residents with information and a few options to keep the message from filling up their Chat History until the issue is resolved.