"lines show areas recently cobbled" (source: Sun sept 2007 now removed)
I'm not sure how accurate the Sun map is.
http://www.mccannpjfiles.co.uk/PJ/CONSTRUCTION_WORKERS.htm has the statement showing the precise location of works left open overnight on 3 May 2007. Both are claimed to be precise markings, and both are on pavements. One is on the SE side of Rua Helena. The other is on the N side of Direita, just W of the junction with Teixera.
In terms of traffic flow, it would have made sense to have Teixera open and 2-way, and the E end of Direita open and 2-way, whilst all the work was strangling the roads SW of these. But what makes sense and what happens in Portugal are not always the same.
We now have 3 ideas to consider. The first is where road works were in action. The second is open trenches. The third is when the surfaces were cobbled or re-cobbled.
On the graphic attached, I have added 2 yellow lines to indicate the trenches that were open on 3 May 2007. Note that 1 beside Direita/Teixera does NOT correspond to what the Sun thinks was recently cobbled, and that strikes me as making little sense.
The improvements were made in 2 phases. Those around the Sun's cobbles, then work paused during the high season, then the rest was done in a second phase.
"The ambitious, but welcome major project of works programmed for 2007 / 8 is now well on its way. Scheduled in two phases, Phase 1 - February 15th to July 15th is now completed. It has resulted in a considerable improvement to the centre of town. Phase 2 - from September 15th is currently underway."