Good news! The cyclepath alongside the railway behind the Arena has been restored, although apparently not officially opened yet. This morning it was blocked by a couple of 4WD who obviously needed to park somewhere.
So it is now possible to circumnavigate the Arena on a bicycle.
And related to that, from Wednesday, 24 July part of the Milligan Street footbridge will be removed, and access between Wellington and Roe streets will be via a new route. As far as I can gather, when approached from the Arena you will continue to ride up the zig zag scaffold ramp, then along the top of the Fremantle line tunnel towards Perth station to a new scaffold ramp opposite the Roe and Lake Street intersection. You then ride down this ramp on to the Roe Street cyclepath.
Slightly inconvenient for Milligan Street users, but amusing for the rest of us.
Perhaps with the bridge gone, the cyclepath will now be extended further along Roe Street to Sutherland Street using the redundent busway.