Online / Live Class Recommendations? - Need to Majorly Boost Score

Hi all!!
I have been studying on and off for the GMAT for around 8 months. I started getting more serious about my studying over the last 3 months. However, more serious needs to get a lot more serious. I took the GMAT Focus exam today and scored around a 435 (pretty low percentile/score across the board in all sections). I am hoping to score above a 645 and need at least a 315 point score improvement.
I think my major issue is actually committing to making progress/focusing on studying. I work full time, have an active social life, and a few hobbies. I'm taking this as a wake-up call to put the social life and other activities on the back-burner for the next 3-4 months and devote some serious time to studying and hopefully be done with the GMAT once and for all.
I have TTP and am about 40% of the way through the course, but I don't think I am utilizing it as best as I should.
Given my low score and issues with ensuring I am making concrete progress while staying on schedule, I am thinking of 2 options:
- Start TTP over (or at least go back and really parse out/understand exactly what foundational facts I am not absorbing from the first 40% of the course)
- Enroll in an in person/online 3-4 month course which meets weekly/twice weekly with homework etc. I think this additional structure/accountability will really help me to buckle down and learn the foundational pieces I need to learn to majorly improve my score.

Looking for advice on these options, if anyone has taken an in person/online course and loved it (I've been doing some research looks like Manhattan prep is recommended? I'm curious about TTP live?)
Also looking for any overall advice please!

Thank you so much!!