For starters, the your TSLA example is a calendar spread and the strategy in your image is a diagonal spread so let's ignore your TSLA example.
The statement in the link is correct. You start with a diagonal spread where you:
- Sell an OTM put at strike "B" which is one month out
- Buy a more OTM put at strike "A" which is two months out
Because you want the underlying to remain in the vicinity of "B", you're neutral.
Here's the part that you missed. When the near month put at strike "B" expires, you sell another one month put at strike at "B". The new position then becomes a bullish vertical spread:
- Short a one month put at "B"
- Long a one month put at "A"
Now you are neutral/bullish because you only lose if the underlying drops below "B".
In your screen shot, you lopped off the rest of the explanation at the bottom of your screenshot. You only included the first 2 lines. The missing excerpt states that the adjustment creates a SHORT PUT SPREAD:
You can think of this as a two-step strategy. It’s a cross between a long calendar spread with puts
and a SHORT PUT SPREAD. It starts out as a time decay play. Then once you sell a second put with strike B (after front-month expiration), you have legged into a short put spread. Ideally, you will be able to establish this strategy for a net credit or for a small net debit.