According to a post on the Nokia Community forums, a staff member wrote, “As the two-year period draws to a close for these smartphones, we remain committed to delivering the best and most secure experiences. So, what does it mean? Once we reach 2 years from the time last market launched these smartphones (and following Operator and regional approvals), the Nokia 8, Nokia 6, Nokia 5 and the Nokia 3 will be able to receive quarterly security patch updates right through to the end of the 3rd year.”
We should note that these updates are talking about security patches. There is no mention of major Android updates so it is unclear if these devices will receive them. However, if you do plan on holding onto these phones for an extended period of time, know that they’ll be somewhat secure at the very least.