The locked lessons means that your work load will increase piece meal. There’s no point to WK letting people dig their own grave with their initial enthusiasm and gung-ho attitude, only to drop their subscription when they are faced with 300 reviews in a day two months later, burning them out on kanji learning.
And who says you can’t be learning things right now? Every item on WK can be freely viewed. You can pre-study however many lessons you want. You can read through all the mnemonics and begin familiarising yourself with it already. You just can’t have it in the WK SRS cycle quite yet.
There are also so many other things to do if you’re itching for Japanese. Grammar. The very vital kana-only vocab that WK, as a kanji-learning resource, will of course not teach. Read book club threads here on the forum to help understand sentence structure.
This site is chock-full of resources. Have at it.