The weekend with longer hours sitting is the straw that broke the camel’s back. The cumulative effect of sitting within the weekend, each day, week etc.
I’d recommend optimizing your sitting position, chair, position when on the phone or computer.
All the details impact.
You can buffer anything until you can’t. No warning you just aren’t able to do it any longer.
Check out Deskbound if you haven’t and the episodes above. All have actionable things you can start incorporating immediately.
Transitioning to a movement station helps when you aren’t able to leave your desk you can still be changing positions etc.