Static IP Changed

When going to a site like ip4.me, my static ip always showed an address that ended in .253, but now it shows with a .254. I called comcast but they said nothing has changed. The supervisor told me sites like that display your gateway address, which she said was the one that ended in .254. I'm no networking guru but is this some BS? I remember in the past it showed .253 and now it show .254. Can a real tech person at comcast help me and let me know whats going on? I cannot access a server that only allows connection from my .253 address.