Van Speijk class frigate sonar types

[PreMars]

I saw on Wikipedia that the ships were fitted with Type 162 and Type 170B sonars when in service. Does that mean the class did not have a variable-depth sonar (VDS) at that time? After the modernization, did the Royal Netherlands Navy update the sonar systems?
By the way, I noticed that the Seaforces website states the ships were fitted with CWE-610 and PDE-700 after modernization, but MilitaryPeriscope website mentions that the PDE-700 sonar on Van speijk class is a hull-mounted version, not a VDS.
I’m quite confused — what exactly was the sonar configuration of the Van Speijk-class frigates?

 

[DWG]

I noticed that the Seaforces website states the ships were fitted with CWE-610 and PDE-700 after modernization, but MilitaryPeriscope website mentions that the PDE-700 sonar on Van speijk class is a hull-mounted version, not a VDS.
I’m quite confused — what exactly was the sonar configuration of the Van Speijk-class frigates?

There were definitely multiple arrangements pre-modification. If you look at the images of Van Galen here, there are at least two stern arrangements, with a large open ramp aft of the Limbo (presumably for a VDS?), and with an enclosed port, open at the top, closed by two doors at the bottom, and with a low protrusion onto the helideck. That latter arrangement is retained by the first four ships post modification. There's a picture of Van Speijk with the sonar system deployed through the port here.

Harpoon 4's High Tide data book (which only has post modernization data, but is usually well researched) claims CWE-610 and PDE-700 VDS, and that Isaac Sweers and Evertsen had SQR-18 towed arrays. Pictures confirm that post-modification Isaac Sweers and Evertsen had a different configuration with a larger port and a noticeably taller protrusion onto the rear of the flight deck.

 

[Privateer]

DutchFleet

AIUI, the EDO 700/701 VDS were commercial derivatives of the SQS-35 VDS used on some Knox class frigates. Evertsen and Isaac Sweers were the only ones fitted with SQR-18. According to the Dutch website, the ships retained the VDS towfish, and the SQR-18 receiver array was attached to it (liked on those Knox class frigates with the SQS-35).

VDS prior to installation in one of the Dutch frigates:

SQS-35 VDS with SQR-18 attached to it:

 

[PreMars]

DutchFleet

AIUI, the EDO 700/701 VDS were commercial derivatives of the SQS-35 VDS used on some Knox class frigates. Evertsen and Isaac Sweers were the only ones fitted with SQR-18. According to the Dutch website, the ships retained the VDS towfish, and the SQR-18 receiver array was attached to it (liked on those Knox class frigates with the SQS-35).

VDS prior to installation in one of the Dutch frigates:

SQS-35 VDS with SQR-18 attached to it:

Then did they have VDS before their midlife refit? If so, what was the VDS model type?

 

[Privateer]

Then did they have VDS before their midlife refit? If so, what was the VDS model type?

They recieved the EDO VDS prior to the midlife refit (the question is when exactly). There are pictures showing the VDS arrangerment in combination with the Limbo mortar.