I noticed the same thing today. Another problem is also names like 'St Marks Rd' pronounced 'Street Marks Road'
The latter should be a software fix id think and possibly the SH as well. I've heard other systems say 'S H 16' so it may be a case of programming waze to recognise those patterns in street names.
Undecided also. I'd prefer to keep SH than change to 'State Hwy' as it's the standard notation in NZ.
Looking at an earlier post would it work if we have SH-16?
Re: TTS with our highway numbering.