Although Phillips made his recommendations in 1622, very little work was carried out over the following five years. The Irish Society and the Crown disagreed about who should pay to strengthen the fortifications.
In 1624 a Royal Commission pointed out that Derry, in its present state, was vulnerable to attack by the disaffected Irish who could use itas a base to regain possession of the Inishowen area. The Privy Council asked the Irish Society to undertake the necessary work to pre-empt this potential threat.
The Irish Society agreed to build the guardhouses, the platforms and the sentinel towers, but denied responsibility for any other improvements. They argued that according to the Articles of Agreement of 1610 they were not under contract to provide, 'ordnance, carriage (mountings and wheels for the cannons), powder, shot and other furniture thereunto appertaining'. Nor did they feel obliged to dig the flooded ditch which they saw as 'work of exceeding great charge and little use'.

Thomas Raven’s 1625 plan of the city showing his proposed additional fortifications.

The Crown drew up 23 more Articles in 1624 to guarantee that the overdue work was done. The Irish Society instructed its agent in Derry to ensure that the work be 'speedily performed'. Amid the controversy over the implementation of improved fortifications, Thomas Raven, then employed by Phillips, proffered a map of the city (circa 1625) incorporating a plan for additional defences. The prominent new features comprised an outer wall, extending from a point just above Ferryquay Gate, linking up with a ditch stretching the length of the bog area. However, the scheme, which would have proved invaluable for the besieged during the ordeal of 1689, unfortunately fell foul of the ongoing financial wrangling was never seriously consider. In 1626 Philips was again reporting that defects still existed and in 1628 a Royal Commisiion concluded that the city was still not adequately defended as it was open to attack from all sectors.