# Sliding window protocol when number of packets is equivalent to the window size

I am currently taking a course in computer networking and I am curious about the following situation:

Given $n$ packets and a window size of $n$ (i.e., the number of packets is equivalent to the window size), what would happen in the following scenario?:

Packet 1 is sent by Host A and the corresponding ACK is received. Do the window boundaries need to be updated to $[2:n + 1]$ or would it remain as $[1:n]$ (as there would be $n - 1$ remaining packets (strictly less than the window size, $n$)?