Welcome to FT!

​​​​​​What class seat are you looking to book?

Generally easier to find Y seats than J.

In response to your last question, the award seat has to be available.

You could use the strategy of booking a date in the range of your acceptable dates which may not be your first choice but that you can make it work with your schedule, and doing so on a flexible award redemption so that later, you can switch without penalty/fees, if seats become available on your ideal date.

For example, I booked the following J flex route for 2024
yyz-ist (stopover) -sin (destination)-ist(stopover)-waw-yyz

I don't want my second IST to be a stopover but thats all I could find currently, but as time goes on, if I find a flight that works to make my second IST a layover instead, I will switch with no additional cost or fee because I booked J Flex on a partner award redemption.

Another tip, with an all partner reward redemption, book the flex option initially, and as you get closer to finalizing your trip, you can call in and switch to the lowest option and get a points refund, in my case I'll be flipping from JFlex to JLo, getting a difference in the points refunded.

Good luck with your journey as you begin to explore the vast knowledge base surrounding award redemptions.