I already have a 5 device subscription and I want to add a 6th device. It is unclear how I can add this device to my subscription which appears to replace my existing 5 device subscription. Will the remaining time on my current subscription be lost if I activate a new 6 device subscription?
To answer your question, yes you may lost the remaining days from your old serial number once you activate a new 6-device serial number because, Trend Micro serial numbers supports a completely independent subscription.
However, we can consider transferring the remaining days from your old serial number to the new one. Kindly update us through this thread once you have activated a new serial number and we'll take care of it for you.