Moving from AVG to OBP - How to estimate league points?

[staz]

5x5 mixed league (see sig) 3-year league average for points earned in the batting average category:

12 - 0.279
11 - 0.276
10 - 0.273
9 - 0.271
8 - 0.269
7 - 0.266
6 - 0.264
5 - 0.263
4 - 0.262
3 - 0.260
2 - 0.259

... but we are moving from AVG to OBP for 2017 and I want to have SOME idea what the end-of-season OBP points might look like.

Guessing it's not as simple as adding 0.065 to 0.070 to each?