What Type 31 upgrades mean for the escort pipeline

What upgrades are likely for Type 31, and how do they affect the Royal Navy's escort program?

Mark 41 VLS is the firmest upgrade, but sonar changes and later Type 32, Type 26, and Type 83 work all compete within two escort production lines.

Type 31 is already due to receive Mark 41 VLS, although its eventual missile fit is still unsettled. Its current form does not readily accept a towed-array sonar, and Type 32 is expected to come from the same low-end escort line rather than become a wholly separate ship. On the high-end line, every added Type 26 extends the wait for the Type 83 destroyer that must replace Type 45. Electronics can be renewed, but repeated major upgrades take ships out of service, so longevity on paper does not remove the availability problem.