As others said, you're not going to be able to raise a small retic on a modified feeding schedule. The animal will get to whatever size it will get, which may be small, or may be large.

I have a female, who is roughly 11.5'-12' at 6 years old. She's closing in on 40 lbs, but I don't have an exact length recording. About 10 lbs ago, I had her in the hallway and she was definitely over 11' and under 12' so I've been going with the 11.5' estimation. But she's also nearly put on 10 lbs now, so I guess it's time for another attempt. lol

When I first got her, she was 6 months old, 150 grams and 3'. She was half the weight of a 3' male I bought a few years ago and then rehomed due to issues outside of the snake. The breeders were feeding her a single fuzzy mouse every 2 weeks. I believe I tried her on mice for her first meal just to make sure she'd eat, and then quickly moved to rat pups. Then, up to weaned rats and then smalls soon after. I was trying to keep to a 10-20% of body weight rule at the time. I stuck to her 14 day schedule for a bit at first, and she still gained 1.5' in 6 months. Then, I went to weekly for a short time until I got her onto rabbits/Guinea pigs. From there, I moved her onto a 3-4 week schedule. She's been eating 3-5 lb rabbits or chickens for awhile now, on a once a month schedule. 5 lb meals still leave a huge lump, but it's hard to get proper-sized chickens and rabbits without raising my own. Rodent Pro doesn't seem to keep to their sizing very well, and I haven't had much luck getting any kind of feeder from people on CL. But even at 6 years old, she is still gaining noticeable length and girth. She's getting close to filling up the holding tub I keep her in while I clean her cage, and at the beginning of this year she just barely covered the floor of it with some gaps all curled up. Now she goes up beyond the halfway point and has no visible gaps to the floor when at rest.