I learned system.tag.read and write have been replaced by system.tag.readBlocking and writeBlocking. I am wondering if there is a version of Ignition where, if we upgrade to said version, we need to worry about instances of the deprecated functions breaking entirely and needing to be rewritten? We are on version 8.1.18.
IA tends to keep deprecated functions around for a really long time. They just don't get much love if bugs pop up, and they are deliberately removed from the documentation.
I'd not worry about old code. If you make sure new code or updated code uses the modern functions, the deprecated stuff will likely be gone before it matters.
We'll also never remove functionality (outside of critical security issues) in a "minor" version - as in, any 8.1 upgrade is absolutely going to be fine. We have no plans to remove these specific functions in 8.3, either, meaning you're set for at least the next several years.
Awesome, thank you for the quick answers.