I currently have a successful bridge with php 2.018 and cpm 1.3.4. However I want to upgrade to 4.2 whats the best plan of attack. Will I have to rebridge?
yes, read the docs for details.
To avoid confusion, please don't drop the first number of the version number. Maybe there will be a 3.4, which is way different from 1.3.4. It's like asking about upgrading from Windows 5 to 9.
But maybe that's just me, who also writes out the four digit year. I think it's a result of being an IT intern before year 2000 and having to help the company prepare for/deal with the millenium bug... Don't want another intern having to deal with that when 2100 comes around.