Season 1 vs Season 2 Confusing

[Moudo-sunstrider]

According to the worldofwarcraft website , the achievements etc have the last D-Day when season 1 ends, which is normal. However, the difference between the war within and DF etc, is that the season tied to these achievements finish just before season 2 starts, not the 11.1 starts. Eearlier, it always ended when the patch started.

If this is intended, then for example delves, will have its old S1 system with tier 1-11 until 4th of march when S2 goes live. Does that mean that we will not do 11.1 Delves until the season actually starts (the week after 11.1 goes live)?

[Punyelf-draenor (Punyelf)]

The War Within Season 1 wraps up with the release of the Undermine(d) content update. If you’re a completionist, then this handy list of all the things that will become unavailable or change with the release of The War Within Season 2 on 5 March is for you!

Last Chance for The War Within Season 1 Achievements and Rewards

[Last Chance for The War Within Season 1 Achievements and Rewards] The War Within Season 1 wraps up with the release of the Undermine(d) content update. If you’re a completionist, then this handy list of all the things that will become unavailable or change with the release of The War Within Season 2 on 5 March is for you! View Full Article

As per the blue post you have until the Season start. So 5th March.