As title if I have data in Json as below

```
{ 
  "label": "btmlabel",
  "items": [
        { "mydata":"bla", "btmlabel":"22 April 10.34AM", "data":[{x:1,y:1},{x:2,y:3}]}
       ]
}

```

Is that possible for me to modify the data as below... 

```
{ 
  "label": "btmlabel",
  "items": [
        { "mydata":"bla", "btmlabel":"22 April 11.00AM", "data":[{x:1,y:1},{x:3,y:4},{x:4,y:5}]}
       ]
}

```

Much appreciate for any help thanks.