Could Britain equip the Grand Fleet with improved shells in time?

Could enough improved shells be made to equip the Grand Fleet before Jutland?

Yes. Using the historical programme as a benchmark, an earlier discovery gives Britain enough time to replace ammunition across the fleet, rather than supplying only a few ships.

Orders for trial shells in May 1917 were followed by mass production in December and fleet delivery in April 1918. That gives roughly eleven months from trial orders to delivery, while the counterfactual allows eighteen months to accommodate slower progress. The historical programme supplied enough improved ammunition to equip the Grand Fleet and support training. Britain's naval industry could replace ammunition across the fleet once directed to do so.