I would meet to get feedback on the pitch if you need it / feel they will offer it. If you feel you have received the feedback you need, and they are now just interested in investigating an investment, I would schedule the meetings for the week before or after Demo Day so you can drive a process efficiently with your time.
Here’s an email response to send to investors if this is the case:
Thank you for your interest in meeting.
Right now, we are heads down on customers and product. We are happy to invite you to our Demo Day when we will kick off our institutional raise. If that's of interest, please fill out this form, and we will extend you an invite. We can also set up a meeting with you immediately before or after our Demo Day if you like.
We are taking a limited amount of capital in now in advance of our Demo Day. However, we will not be able to meet given time constraints. If you would like to invest without having a meeting, we can send you the Alchemist SAFE that we are taking a limited amount of capital on now if you are able to make a quick investment decision with no meeting / limited information.
My best,
[Your Name]