While replacing rusted, leaking pipes to wx202 pressure tank, I noticed the lower dome appeared to be rusting through and what I think is the liner is starting to show. I told my cousin(who's house I was working at) that it should be replaced relatively soon, however, I couldn't tell him the urgency of the situation as this is not something I work on much. Is this a problem that should be handled in days or can it wait a month or so. It's probably been like this for a while now. Thanks in advance for your opinions. Dennis