Time slice issue in EQUZ table

I am currently facing an issue where new time slices are being created for devices in the table EQUZ.

For example. Lets take a device 1234 which is installed on 01.01.2013 and is valid till 31.12.9999.

If I double click and go inside the device to check the valid from date I can see a new time slice has been created.

Below is a screen shot that you can see.

This is not letting me to remove the device from the installation. Is there any way to correct this issue other than correcting the time slice in the EQUZ table? Any suggestions would be greatly helpful.