We don’t have any rules that address this, however, if you change blades, you need to reinstall the stock blade and correctly adjust the guides when you are done. There are videos on Youtube that address how to adjust the guides, here’s an example:
Changing the blades is a hassle, and as Matt said, the difference between the 3/16 blade on the blue saw and a 1/8 blade isn’t much, but if you want to do it, and are willing to reset the guides correctly when you are done, then the blue (3/16) and White (3/8) saw are both 14 inch saws with 105 inch blades. The large saw is a 20" with 142 (I think) blade.
The biggest problem we have with the Bandsaws, is people forcing their stock into the blade. This dulls blades fast, breaks blades, or kinks them, and 95% of the blades we replace were ruined from this.
If you are feeding stock at the correct speed, you will never ever feel the blade (because its cutting away the wood as you feed it). If you start to feel the blade push back, and have the sensation pushing harder will speed it up - you’re in the process of destroying the blade. Slow down.