Don't worry too much about your different test results.

=> DPD tablet testing is NOT reliable at all with the chlorine levels you are encountering. Don't use it.
=> Syringaldazine (test strips -- blue/purple color) are reliable, but not very precise.
=> OTO (yellow / orange / brown color) is reliable and slightly more informative than the strips: use that.

The ONLY tests you need worry about right now are your PM and AM tests. Until your post chlorine-dose PM test equals your AM test result -- keep chlorinating every evening. You don't even need to do more than that, once you receive the K2006, until your chlorine is stable overnight. OTO is cheap and gives you enough information to get you through this stage of the process.

Ben