I found information online that further explains molts. Here's what was stated:
L1 = Develops inside the egg
L1/H = Hatches
M1/L2 = Has 1st Molt, is at Larval Stage 2
M2/L3 = Has 2nd Molt, is at Larval Stage 3
M3/L4 = Has 3rd Molt, is at Larval Stage 4
M4/L5 = Has 4th Molt, is at Larval Stage 5
M5/L6 = Has 5th Molt, is at Larval Stage 6
M6/L7 = Has 6th Molt, is at Larval Stage 7
M7/L8/Immature Adult = Has 7th Molt, is at Larval Stage 8, is Sexually Immature
Mature Adult = Is Fully Grown, is Sexually Mature
So I was right about most of it, such as when they first hatch they are at L1. The only thing I didn't know of is that going from an immature adult to a mature adult counts as a life stage, so my Tenodera sinensis' and Angustipennis' had 9 life stages rather than 8, but have molted the same amount of times as I predicted.
So, Zeep will be at M7/L8, an Immature Adult, once he molts for this last time. Then in about 3 weeks he'll be a Fully Grown, Mature Adult.
Unfortunately, the Immature Adult female I had, Curious Georgina, mis-molted and is now deceased. So he doesn't have another Sinensis to mate with. Though, I have a Mature Adult female Angustipennis which he could possibly breed with. Would they be compatible, and would the female lay a fertile ootheca afterward? Would it look like a Sinensis ootheca or an Angustipennis ootheca? Would it look like a combination of both? I imagine it is definitely a possibility that it would work out, as they are of the same genus. Though, it would be important that I kept the nymphs and did not release them into the wild as this is actually illegal. I would literally be the creator of a new species and if released, they think it may cause problems. I would think that unlikely but I will follow the rules none-the-less and refrain from releasing any nymphs into the wild. Or selling them. I wonder what I would name the species? Let's first take the species' names and figure out their definitions. "Sinensis" means "native to China" in Latin and "Angustipennis" means "having a narrow wing". So let me find the latin word for... "hybrid". Which is "hybrida". If it truly worked, that's what I would name the species. Tenodera hybrida.