https://www.canadavisa.com/canada-immigration-discussion-board/threads/sa-pre-arrival-letter.732747/post-9858653How long does NDVO usually take after pre-arrival letter? Also, what does the pre-arrival letter indicate?
It concretely means what the text in it says - you are eligible for pre-arrival services. It also indicates the file is moving forward, and next steps probably before long - but nobody can tell you how long those next steps might take.