Let's roll out the last formula used for cardio care. Fuck that was a long time ago
full vacation, plus sick days - no matter how many you have used. For each year of service you received 1 week. For each year you are over 40 yo, you get a half week.
Add it all up - those are the weeks of continuation. If there is a WARN, then the clock starts w 60 days + the result of the above formula. WARNs are announced and very formal.
Of course - all that can change and probably will. AbbV is generous.