At present, before you deploy each of these switches, you need to configure a computer to 192.168.88.0/24 to get the web UI, and use that to set the switch's address according to where it will be going. (And if you have pre-configured several switches for various locations, don't lose track of which one goes where!)
With DHCP, you could drop any switch into any location, and its web UI would be accessible straight out of the box. With static DHCP leases, you could even pre-configure the router to give it the desired address as soon as it appears--and if its role is a simple switch, it's up and running without even using its web UI. If DHCP times out (e.g., you aren't using it), it could always default to 192.168.88.1 as a fallback.