I would personally say that maybe it's not as much time to move on as it is time to take a break from practising it. From my own personal experience, what helped me is to try to get as fast as possible and make my muscle and fingers learn the pattern as much as possible. First step is memorizing it so you don't have to think about it which I feel like you obviously have already done.
Then you raise up the speed to be as high as you possibly can and when you start feeling like its blocking and not advancing and that no matter how much you practice, you just don't see progress, then that's when time comes to move on from that specific pattern (in this case solo) and make your muscles work on something else. Why? Because that way they will have time to assimilate what you try to do and will be better prepared. It's a bit more spacey concept because it deals with subconscious, reflexes and muscle memory but what I find is that once you come back to it after, let's say in my case it's generally 2-3 weeks, you sort of have forgotten it a bit and you have to relearn it and so you go back to a smaller speed but then you start to raise it back up again and then often I come to realize that the part I was struggling with has become easier and then I can go faster.
I am not a doctor obviously but I really went and looked up the link between the nervous system and music and it's relationship with the brain and it helped me optimized my practice a lot because what happens is that the muscles (in this case fingers) will already know what they have to do and will get faster because they just know it. How many time have you been playing fast and then you start looking at your fretboard and think about what you are doing and suddenly you fumbled? That's what happens when you conscioucsly go and interrupt the finger's own ''intelligence''
It's sort of the same behaviour as your brain when studying. How many time did it happen that you sat down and started studying something and then you take information in for 30, 40, 50 min and then your brain starts to feel like it can't take anything anymore and that nothing goes in. That's often because it needs time to assimilate what you just fed him. And so it's why a lot of people advise to study for 45 min and take 15 min break doing something that will make you think about anything else. In that 15 min frame time, if I understood correctly, your brain will then start to assimilate the concepts and won't be overwhelmed by you constantly trying to feed him information. And then when you get back to studying, you will feel fresher and more open to assimilate new information!
Obviously muscles work in a different manner and more often, slower than the brain. Then again, it really depends from one individual to the other as people's body are different and it also depends on how you generally stimulate your muscles. So while I can't tell you exactly what will work for you, I am just sharing my trick and the method to my madness of learning 6 instruments at the same time and still progressing!
I hope this somewhat makes sense!
