Is there any documents that describe migration from Ort::CustomOpApi to current API?

[RiverLight4]

Hello,
I'd like to use MMDeploy to convert pytorch model into onnx, but it supports onnxruntime <= 1.15.1 because MMDeploy Custom Ops relies on ort::CustomOpApi. (see open-mmlab/mmdeploy#2465 , open-mmlab/mmdeploy#2779 )
I'm afraid that I cannot find any documantation about porting from old ort::CustomOpApi to new APIs to estimate how difficult it is.
Is there any document or issue that describes briefly?