ShiroKuro That sounds really bad ShiroKuro …. If it were me (and it is not) I would certainly not continue at all with the sub. Period. (my own personal opinion)
I have kind of a rule of thumb that I use for myself whenever looking for a piano teacher; it is very simple - I need to be very truly inspired by the person, i.e. as in I need to hear him/her play and really like what I hear (particularly true for jazz but also fully applies to classical no doubt). Preferably live - for example attend a recital or performance of that person, or ask him/her to play a little for you, or worst case find a recording (YouTube or other). The premise is that this person will teach you what they already know and how they do it, so if you do not like what you observe or if it does not align very much with your aspirations as a pianist, it will likely affect your own level of commitment and accomplishment at the keyboard.
I have had teachers which inspired me at the get go, but after progressing with them for a few years while enjoying my lessons and hearing results, I sometimes reached a point where I could no longer feel that I had that connection. That was a very clear signal that I needed to move on.
Given the time (several years) that you have been playing and based on your experience, you highly likely would be able to feel yourself when you find a good match. For someone just kind of starting out, my thoughts may be ill-advice.