The latest trial is actually 50 (clears) and 2 others have been so before it.

It's not just about the mount though. You're also gearing up, starting with accessories and then moving on to weapons. You win some. You lose some. You have ample time to do it. If you don't like it, you can always just wait on it. Everything in previous expansions goes much faster and by that time the drop rate has increased by whatever piddly amount. On the moogle tome events, they'll have one or two you might have missed.

tldr; no pressure