https://www.crazyguyonabike.com/doc/...id=125743&v=3b
has info on accommodation options. I suggest a tent and sleeping bag are a good insurance, especially in touristy places where accommodation may be fully booked but a campsite is usually possible for a cyclist.
The peak holiday season for locals has passed but there are still lots of overseas tourists clogging up many places. You will need to call and book ahead at many places.
Buy a sim card and monthly plan (about $16 for 1.25Gb and 200min calling, unlimited text from Skinny)
And don't cycle SH1 from Christchurch to Timaru.
https://www.crazyguyonabike.com/doc/...id=126092&v=3X