Actually D+ never had access to the SL. The SLs went in as replacements for the almost defunct CLs. Still find a few CLs on the smaller ships, but all the new ones now are SLs. On the ships that still have the old CL, D+ were permanently kicked out a few months ago. And now even Pinnacles don't have access if their numbers are over the "threshold" determined by each ship.
Since the voucher program went in, we no longer venture into the CL or SL...or even DL except for early morning coffee. Like you, our go to for happy hour is usually the VCL.