When to increase soil block size?

Hi all,
This is the first year I have done soil blocks and so far things are looking great. I'm wondering when it is time to go from 3/4" blocks to 2". I know there are a lot of variables so I am just trying to see what other gardeners are doing. I think my blocks need more time because the roots dont seem that well developed because the blocks are still rather fragile. How do you decide when to step up to 2"? They are just starting to get their first set of true leaves.

Also, I am bottom watering and have noticed a lot of roots are growing out the bottom. I am concerned  that the roots are going to get tangled making them difficult to separate.  Have you ran into this issue?

This is my first year with soil blocks too and I haven't started any in the 3/4" yet but I have started some in the 2" and What I have been told by the folks who got me going in this direction is that if you are going up to a larger soil block then you should go up once you have some root growth out of the smaller one.

Hi,

I moved from soil blocks to 1 gallon grow bags,  I first started with net cups, but then I moved to the 1 gallon bags that I sew up on a sewing machine.     The grow bags have all the advantages of air pruning but have the bonus of being easier to move verses the soil blocks.      1 gallon size works well for me because you don't have to worry so much about transplanting.

This is my video I did when I was using netcups.