Honestly avoiding it for now. I love undertale but I have no idea what this fan game is. It kind of came out if nowhere for me. I'll need to evade too much info on it as, if and when, I play it I'd want to know nothing.
I only have capacity for one emotionally driven game every few months. With Undertale I waited untill I had some time off because I feel that needed to be experienced without long breaks. A fully emmerive experience. This leaves me emotionally dead for a few days after and I need to be alone for a bit. Undertale isn't the only experience to do that to me but emotionally driven gameplay is devastating when done right (in a good way I guess)
This year's holiday break, on many recommendations it's going to be Omori. Maybe I'll try Yellow in March though. If life doesn't get crazy.