Found something interesting here fellas. The Eastern Bay Link (a4232) looks like it will be completed in due course as an infrastructure improvement to complement the Cardiff LDP (Local Development Plan). It seems to fly over the Ocean Way roundabout, (could make sense why they're clearing trees in the middle of it) and then heads along a route that perfectly fits Rover Way. To me it seems like they are dualling rover way and (hopefully) grade separating it.
Whats interesting about the map below is that a large part of the A48 (in RED) will become the easternmost section of the Eastern Bay Link (in BROWN), and will continue as the EBL until it reaches Pentwyn. Three major junctions, from Queens Gate, all the way up to the A48, are all highlighted in yellow, meaning ''Strategic junction improvement' which to me, tells me that this will all be grade separated. If that is the case, then the a4232-a48 junction next to Pen-y-lan will have to me HIGHLY modified to support high quality dual carriageway as the main route underneath the junction will have to be realigned to the future EBL.
This document was released this time last year, 6 months AFTER phase 1 of the EBL started, so this document is well in date.