The Android security update situation is confusing and messy despite Google's best efforts, such as mandating companies to provide at least two years of security fixes. Samsung, the largest Android device maker in the world, has just modified the list of devices it supports with security updates, and there's been some shuffling around with a few phones getting kicked off.
Of note is the addition of three models to the list of devices being promised monthly updates: Galaxy Fold, Galaxy A50, and Galaxy Xcover 4s, the last being surprisingly upgraded from quarterly updates.
Three devices — the Galaxy A20s, Galaxy Tab A 8, and Galaxy Tab Active Pro — were added to the quarterly list, while the 2017 Galaxy Tab A was demoted from quarterly updates to the vague "other" category. That means it'll get updates, just not on any preset schedule.
The Galaxy Xcover 4 was also added to that "other" section and finally, the following devices were removed from the list entirely: Galaxy A5 (2016), Galaxy A3 (2016), and the Galaxy Tab S2 L/S Refresh.
In an ideal world, all Android devices shipped by Samsung within the past two years should be included in the Monthly category and not just the most recent flagship and mid-range devices. Due to the nature of Android and Google's lack of firmer enforcement, however, this is the way it's going to be for the foreseeable future.