What are the advantages of the AJK-16 VLS over the UVLS, in the context of the 054B? Having 18 meters of beam (which is the same as the 052Ds, by the way) should have enough space to fit ULVS, which can offer much larger available munition volume than the AJK-16.
Honestly speaking, with the 054B's hull being considerably larger than than that of 054A, I don't see how sticking with AJK-16 would be better for the 054B than completely switching over to UVLS at this point.
It can use the same VLS canisters for the 054A. If the 054B will use U-VLS but with the high possibility that it will use the longer ranged HHQ-16F, the HHQ-16 will have to use a new canister for the U-VLS, which can either be cold or hot launched. The land systems HHQ-16 are all cold launched by the way. For this reason it can also use the YU-8 canisters for the 054A for ASW work.
If the PLAN is willing to change the canisters for the HHQ-16 and YU-8, which in other words, have the HHQ-16 or YU-8 prepacked in U-VLS and AJK-16 canisters, they can forego this issue. But this is logistics. Having the same missile offered in two versions of two canisters sounds messy. While much of the 054A fleet will still use the older HHQ-16, the latest and last batch with the AESA illumination radars is likely to be using a new HHQ-16 version, and this is probably the same one that is going to be used on the 054B.
I think its likely the 054B will use the new HHQ-16, as I don't think you are going to develop a new version of the HHQ-16 that's good only for a handful of ships. The new AESA illuminators have also been spotted on the same test ship as the new dual sided AESA is, so this is a good pointer that the illuminators are meant to work with this new radar. If the new HHQ-16 has ARH option, a U-VLS canister also creates an option that it can be used on the 052D and 055. If the new missile has the range as what its land based variant has, which is 160km, that makes it a serious option.
The problem is whether the AJK-16 can use quad pack SAMs. If you do not have a quad pack SAM specifically developed for it, the VLS would be without one. There's a quad pack SAM being developed for the U-VLS. I also think there is a potential candidate for a quad pack on the AJK-16 based on the land based LY-70. But I get the feeling that quad pack SAMs are not a high priority for the PLAN, nor do they think highly of it, or think that its that effective, otherwise they would already have one deployed many years ago. So the idea that the 054B may use U-VLS to use the same quad pack SAM as the 055 and 052D may not be a strong one especially if the ship is already topped off with HHQ-10. Simply said, the issue of quad pack SAM may not be as high a priority with PLAN planners as they do with internet forumites.
The issue of using U-VLS on the 054B comes with standardizing the use of YJ-18 as the preferred antiship missile of choice by the PLAN. As we have seen posters of YJ-83 with U-VLS on Zhuhai, it maybe possible there maybe a YJ-83 option for the U-VLS instead of using slant mounts. The use of YJ-83B with the optical or thermal seeker would be for littoral water anti-shipping, as the littorals are a problem for radar seekers, and it can be used against land targets, such as antiship missile TELs located on rocky islands like what Japan is planning to do.
You prefer that your saturation antiship missile attacks must be the same as the rest of the fleet, 052D and 055, so they all arrive at the same time at the enemy fleet to overwhelm its defenses. For that reason, its much easier to coordinate a mass of antiship missiles with the same speed and flight pattern, versus lets say a mix of subsonic (YJ-83, YJ-62) and supersonic missiles (YJ-12, Sunburn). The result of mixing is that the supersonic missiles will reach the enemy fleet first, and will get shot down piecemeal. Then the subsonics will arrive many minutes later, and they won't be as dense compared to say, if the entire mass is entirely subsonic. With a mixed supersonic and subsonic mass, you have to time both wave of launches so they both arrive at the target at the same time.
So I think this is a good reason for the 054B to have the YJ-18 and by extension, the U-VLS.
Then there is the question of using the HHQ-9B on the 054B. I don't think the dual sided rotating radar will have the same performance as the fixed Type 346A and 346B radars used on the destroyers but having something is better than nothing, and it can still give the ship the option to engage something beyond the range of even the extended HHQ-16, this being the zone from 160km to 300km. The use of CEC panels, which is very likely to me, since the CEC panels also appeared in the lantern dome test radar in Wuhan, means it can share the sensory data from another ship equipped with such, like the 055, or the three carriers. If the target is not visible on the 054B's radar but is visible on the Fujian 003's radar because of the radar horizon, using CEC, the 054B is reading the Fujian's radar input and launches missile towards that target. Having the HHQ-9B option on the 054B means using the U-VLS.
So there's two big reasons for using U-VLS on the 054B versus the logistical inconvenience of putting HHQ-16 and YU-8 on U-VLS in addition to AJK-16. But at the same time, there is another plus in putting HHQ-16 and YU-8 on U-VLS and that it opens the use of both missiles on the 052D and 055, providing only the HHQ-16 version with the ARH seeker. The use of U-VLS on the HHQ-16 new variant and the YU-8 sounds wasteful considering the empty space left, but this seems to be a small price to pay for a tremendous opportunity. After all, the war in Ukraine has highlighted the risk of running out missile stocks. Having stocks of HHQ-16 ARH as a backup in case of the HHQ-9B running out during a hot war.
